NCERT Solutions for Class 3 Maths Chapter 03 Double Century

Chapter 3: Double Century

Question 1. Look at the picture. Estimate and write the number of each of the following objects.
a. Oranges : .................
b. Bangles : .................
c. Laddoos : .................
d. Barfi : .................
e. Bindis : .................
f. Bananas : .................
Answer: Based on the picture, here is the count of each item:
a. Oranges: 22
b. Bangles: 50
c. Laddoos: 28
d. Barfi: 22
e. Bindis: 75
f. Bananas: 36
In simple words: We can count the fruits, sweets, and decorations in the picture and write down their exact numbers.

Exam Tip: For estimation questions, try counting small groups (like groups of 5 or 10) to make your guess more accurate.

Question 2. Answer the following on the basis of the Snakes and Ladders board:
1. Which number will you reach if you take the ladder from 13?
2. If you are on the snake at number 25, which number will you reach?
3. You are standing on 96. Which number on the die will take you to the snake's mouth?
4. Show the number written on the tail of the longest snake using bundles and loose sticks.
Answer: Based on our snakes and ladders board:
1. If you climb the ladder from 13, you will land on 50.
2. If the snake bites you at 25, you will slide down to 2.
3. If you are on 96, rolling a 3 will land you on 99, which is the mouth of the snake.
4. The tail of the longest snake is at 53. In bundles and sticks, this is 5 bundles of ten sticks and 3 single sticks.
In simple words: Ladders take you up to higher numbers, and snakes slide you down to lower numbers on the board game.

Exam Tip: Find the exact number of the snake's mouth on the board first, then count back to see what number you need on the die.

Question 3. Let us Think. I am a talking Pot. Tell me any number, and I will tell you the next.
• I said 39, Pot said ............
• I said 63, Pot said ............
• I said ......, Pot said 90
• I said ......, Pot said . I said 97, Pot said ............
• What is 100?
Answer: Here are the numbers from the talking Pot:
* When we say 39, the Pot says 40.
* When we say 63, the Pot says 64.
* To get 90 from the Pot, we must say 89.
* When we say 97, the Pot says 98.
* What is 100? 100 is called "one hundred." It is the number that comes right after 99.
In simple words: The talking Pot always adds one to any number we say. One hundred is the number right after ninety-nine.

Exam Tip: The "next" number means adding 1 to the current number, which is also called the successor in math.

Question 4. Let us Do. Question 1 : Fill in the blanks. (Making 100 table with bundles)
Answer: We can complete the number sentences for making 100:
* Row 1: 70 and 30 makes 100.
* Row 2: 80 and 20 makes 100.
* Row 3: 50 and 50 makes 100.
In simple words: We can combine different groups of ten sticks to make exactly one hundred sticks.

Exam Tip: Keep in mind that 10 groups of ten sticks always make exactly 100 sticks.

Question 5. Question 2 : Use matchstick bundles and a ginladi to make 100 in different ways. Fill the table below.
Answer: Here is how we make 100 using different pairs of numbers:
* 60 and 40 makes 100.
* 45 and 55 makes 100.
* 75 and 25 makes 100.
* 15 and 85 makes 100.
* 25 and 75 makes 100.
* 65 and 35 makes 100.
In simple words: We can add many different pairs of numbers together to get a total of one hundred.

Exam Tip: If one number is given, subtract it from 100 to quickly find the missing number for the blank.

Question 6. Question 3 : Write numbers in the blank space inside the flower petals so that the numbers in each petal add up to 100.
Answer: We can fill in the blank petals so each pair sums up to 100:
* First Flower (Middle is 100):
* 60 + 40 = 100
* 30 + 70 = 100
* 37 + 63 = 100
* 19 + 81 = 100
* 75 + 25 = 100
* 45 + 55 = 100 (Given)
* Second Flower (Middle is 100):
* 9 + 91 = 100 (Given)
* 34 + 66 = 100
* 86 + 14 = 100
* 99 + 1 = 100
* 10 + 90 = 100
* 100 + 0 = 100
In simple words: Each petal has a pair of numbers that add up to one hundred when joined together.

Exam Tip: Double check each flower petal by adding the two numbers together to make sure they equal exactly 100.

Question 7. Let us Explore. How many are 100? Question 1 : Open a full box of matchsticks. Estimate, count, and see how close you are.
Answer: Here is the result of the matchstick estimation:
* My estimated guess is 40 matchsticks.
* The actual count is 32 matchsticks.
* My guess was very close! The actual count was just 8 sticks less than my guess.
* Since each box has about 32 sticks, we need 3 boxes to get close to 100 matchsticks (32 + 32 + 32 = 96).
In simple words: I guessed 40 sticks, but there were 32. We need three full boxes of matches to get close to 100 sticks.

Exam Tip: To estimate, count 10 sticks first to see how much space they take, then estimate the rest of the box.

Question 8. Question 2 : Take a handful of seeds like kidney beans, chickpeas, etc. Estimate and count them.
Answer: Here is the result of the seed estimation:
* My estimated guess is 12 seeds in one hand.
* The actual count of seeds is 10.
* We would need 10 handfuls of seeds to reach close to 100 seeds (10 handfuls × 10 seeds = 100).
In simple words: One handful has about 10 seeds. So, we need ten handfuls to collect a total of 100 seeds.

Exam Tip: Try this activity with different seeds like peas or beans to see how the size of the seed changes your count.

Question 9. Let's observe the table and learn to write numbers beyond 100. Fill in the blank spaces. Fill the blank spaces on the number line given at the edge of the page.
Answer: We can fill in the missing numbers in the list:
* 100 and 3 makes One Hundred three (103)
* 100 and 4 makes One Hundred four (104)
* 100 and 5 makes One Hundred Five (105)
* 100 and 6 makes One Hundred six (106)
* 100 and 7 makes One Hundred Seven (107)
* 100 and 8 makes One Hundred eight (108)
* 100 and 9 makes One Hundred nine (109)
Here are the missing numbers on the edge line from top to bottom:
* Between 112 and 114: 113
* Between 114 and 117: 115, 116
* Between 117 and 120: 118, 119
* Between 120 and 124: 121, 122, 123
In simple words: We can count beyond one hundred by adding single numbers, like one hundred and one, one hundred and two, and so on.

Exam Tip: Pay attention to the spelling of number words like "eight" and "nine" when writing numbers beyond 100.

Question 10. Let's continue making numbers above 100 using matchstick bundles and loose sticks. In the table given below, identify the bundles and loose sticks and write the corresponding numbers.
Answer: Here is the completed table showing numbers represented by matchstick bundles:

In simple words: This table displays how many hundreds, tens, and ones are in each three-digit number using bundles of sticks.

Exam Tip: Always check if any column is empty. If there are no bundles of 10, write a "0" in the tens column.

Question 11. Match the numbers with the correct bundles and loose sticks.
Answer: Here are the correct matching pairs:
* 101 matches with: 1 bundle of 100 and 1 loose stick
* 116 matches with: 1 bundle of 100, 1 bundle of 10, and 6 loose sticks
* 110 matches with: 1 bundle of 100 and 1 bundle of 10
* 100 matches with: 1 bundle of 100 only
* 140 matches with: 1 bundle of 100 and 4 bundles of 10
In simple words: We can match each three-digit number with the right group of big bundles, small bundles, and single sticks.

Exam Tip: First count the big bundles (hundreds) and small bundles (tens) to quickly find the matching number.

Question 12. Oh! Talking Pot is back. It will say one more than whatever you say.
• Bholu said 109, Pot said ............
• Bholu said 134, Pot said ............
• Bholu said 105, Pot said ............
• Bholu said ............, Pot said 150
• Bholu said 100, Pot said ............
Answer: We can complete the numbers for Bholu and the Pot:
* When Bholu says 109, the Pot says 110.
* When Bholu says 134, the Pot says 135.
* When Bholu says 105, the Pot says 106.
* To make the Pot say 150, Bholu must say 149.
* When Bholu says 100, the Pot says 101.
In simple words: The Pot always adds one to Bholu's number. So, if Bholu says 109, the Pot says 110.

Exam Tip: Remember that adding 1 to a number ending in 9 (like 109) always changes the tens digit (to 110).

Question 13. Fill the blank spaces on the number line.
100 --- 110 --- 120 --- [ ] --- [ ] --- 150
Answer: The missing numbers on the line are 130 and 140.
In simple words: This number line counts forward by tens. The missing numbers are one hundred thirty and one hundred forty.

Exam Tip: Check the gap between the numbers. Here, the numbers increase by 10, so count by 10s to fill the blanks.

Question 14. Show the following numbers on the number line below.
1. Place an arrow on 125.
2. Make a tree on 112.
3. Make a smiley on 149.
4. Put a cross (✗) on 137.
Answer: Here is how we show each number on the line:
* To show 125, we draw an arrow pointing to the middle point between 120 and 130.
* To show 112, we draw a little tree just after 110.
* To show 149, we draw a smiley face right before 150.
* To show 137, we put a cross mark (✗) between 130 and 140, closer to 140.
In simple words: We can mark different numbers on a line using small pictures like trees, arrows, and smiley faces.

Exam Tip: For numbers like 149, place your drawing right next to the line of 150 since 149 is just one step behind it.

Question 15. Let's now count beyond 150. Extend this table till 200 in your notebook. How much is 200?
Answer: We can count from 150 to 200 by keeping track of hundreds, tens, and ones:
* 150 has 1 hundred, 5 tens, and 0 ones.
* 160 has 1 hundred, 6 tens, and 0 ones (One hundred and sixty).
* 170 has 1 hundred, 7 tens, and 0 ones (One hundred and seventy).
* 180 has 1 hundred, 8 tens, and 0 ones (One hundred and eighty).
* 190 has 1 hundred, 9 tens, and 0 ones (One hundred and ninety).
* Two hundred (200) has 2 hundreds, 0 tens, and 0 ones. It is equal to two complete bundles of 100 sticks.
In simple words: Two hundred is equal to two groups of one hundred. It has no extra tens and no single ones.

Exam Tip: Remember that when we reach 200, the hundreds digit changes from 1 to 2, and the other digits become 0.

Question 16. Let us Do at Home.
1. Fill a small container like a small bowl with seeds such as kidney beans, chickpeas, etc.
2. Look closely at the container to estimate how many seeds are in it. Your Estimate: ........ seeds.
3. Now count and see how close your estimation is to the actual number of seeds. Counted ........ seeds.
4. Guess how many times to need to fill the container to get close to 200 seeds? Your guess: ........ times.
Write the numbers in order on the stones. (150 to 165)
Answer: Here are the results of our seed activity:
* My estimated guess is 50 seeds.
* The actual count is 40 seeds.
* To reach 200 seeds, we need to fill the bowl 5 times (5 times × 40 seeds = 200).
* The numbers in order on the path stones are: 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165.
In simple words: Counting the seeds shows how close our guess was. We can write the numbers in order from 150 to 165 on the stones.

Exam Tip: When writing numbers on stones, make sure you increase the number by exactly 1 for each next stone.

Question 17. Question 1 : Draw jumps of 5 on the number line and write the numbers on the number line in the given spaces.
Answer: The numbers on the line when jumping by 5 are: 105, 115, 125, 135, and 145.
In simple words: When we skip-count by five, we write numbers ending in 5, like 105, 115, and 125.

Exam Tip: Skipping by 5 means the ones digit will always switch between 5 and 0 (for example: 100, 105, 110, 115).

Question 18. Question 2 : Continue jumps of 20 and write the missing numbers on the given number line.
Answer: The missing numbers on the line when jumping by 20 are: 140, 160, and 180.
In simple words: Skipping by twenty means adding 20 each time. The missing numbers are 140, 160, and 180.

Exam Tip: Think of skip-counting by 2 (2, 4, 6, 8) and add a zero at the end (20, 40, 60, 80) to make counting by 20s easy.

Question 19. Question 3 : Fill in the table. (1 less, Number, 1 more)
Answer: Here is the completed table showing numbers with one less and one more:

In simple words: This table displays the number that comes right before and the number that comes right after each given number.

Exam Tip: "1 less" means subtracting 1 (predecessor) and "1 more" means adding 1 (successor) to the middle number.

Question 20. Question 4 : Show at least two different ways of making the following numbers.
a. Use matchstick bundles to make 125.
b. Make 145 using a ginladi.
c. Make 170 on a number line.
Answer: Here are different ways to represent these numbers:
* a. For 125: We can make 125 by placing 1 bundle of 100, 2 bundles of 10, and 5 loose sticks on the table.
* b. For 145: On a bead string (ginladi), we can count 14 groups of ten beads and then add 5 single beads.
* c. For 170: On a number line, we draw a mark at the point that is halfway between 160 and 180.
In simple words: We can show three-digit numbers using bundles of matchsticks, colorful beads, or marks on a number line.

Exam Tip: When using a bead string, always count by groups of ten first before counting the individual single beads.

Question 21. Question 5 : Fill in the empty boxes appropriately.
Answer: Here is the completed table showing numbers, bundles, and number sentences:

In simple words: This table displays how hundreds, tens, and ones make up different numbers and how they can be written in short sentences.

Exam Tip: Pay attention to the special sentences, like "30 more than 150," which is another way of saying 180 (150 + 30 = 180).

Question 22. Question 6 : Mark the following numbers on the number line.
a. 109, 112, 124, 134, 146
b. 155, 163, 178, 189, 198
c. 125, 142, 153, 174, 199
Answer: We can place these numbers on the lines using these steps:
* Line a (100 to 150): Mark 109 just before 110, 112 right after 110, 124 just before 125, 134 before 135, and 146 just after 145.
* Line b (150 to 200): Mark 155 in the middle of 150 and 160, 163 after 160, 178 near 180, 189 just before 190, and 198 right before 200.
* Line c (100 to 200): Mark 125 in the middle of 120 and 130, 142 after 140, 153 after 150, 174 before 175, and 199 right before 200.
In simple words: We can show the correct place of each number on the line by looking at the nearest tens, like placing 109 near 110.

Exam Tip: Use the marked numbers on the line (like 110 or 120) as helper points to find the exact place of other numbers.