NCERT Solutions for Class 4 Maths Mela Chapter 03 Patterns Around Us

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Question 1. How many coconut trees does Gundappa have?
Answer: Gundappa has 81 coconut trees on his land.
In simple words: He owns 81 coconut trees total.

Exam Tip: Count carefully by finding the number in each row and the number of rows, then multiply them together.

Question 2. How do you know there are 81 trees?
Answer: Looking at the image, the trees are set out in a grid layout. I can see 9 trees in each row and 9 rows altogether, so 9 × 9 = 81 coconut trees.
In simple words: The trees form a square pattern of 9 by 9, which makes 81 in total.

Exam Tip: Always describe what you observe in the image and show your counting method with the numbers you find.

Question 3. Gundappa has plucked 5 coconuts from each tree. How many coconuts has he plucked?
Answer: Gundappa took 5 coconuts from each of the 81 trees. So the total number of coconuts = 81 × 5 = 405 coconuts.
In simple words: Since he picked 5 from each tree and there are 81 trees, multiply 81 by 5 to get 405 coconuts.

Exam Tip: Use multiplication to find the total when you know how many of something come from each item and how many items there are.

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Question 4. Muniamma makes plates and cups. How many cups are there?
Answer: Counting the cups shown in the image, there are 60 cups in total.
In simple words: Add up all the stacked cups you see to find 60 cups.

Exam Tip: Count stack by stack or row by row to avoid missing or double-counting items.

Question 5. How many coconut laddoos are there in the trays?
Answer: Looking at the arrangement in the trays, there are 12 coconut laddoos in total.
In simple words: Count each laddoo shown to get 12.

Exam Tip: When counting items in groups or frames, count each group separately and add them together.

Question 6. How many milk pedas are there in the trays?
Answer: The trays show 13 milk pedas in total.
In simple words: Count all the milk pedas to get 13.

Exam Tip: Look carefully at each tray and add up the count from all trays combined.

Question 7. Shirley and Shiv arranged their play money in some nice patterns. How much money is in the first arrangement?
Answer: Looking at the first pattern, the money adds up to Rs.80 in total. The coins shown are: four Rs.5 coins, four Rs.10 coins, and one Rs.20 coin. Counting: (4 × Rs.5) + (4 × Rs.10) + (1 × Rs.20) = Rs.20 + Rs.40 + Rs.20 = Rs.80.
In simple words: Add the value of each type of coin to find the total amount.

Exam Tip: Identify each coin type and its value, then multiply to find the total for each type before adding all types together.

Question 8. How much money is in the second arrangement?
Answer: The second money pattern totals Rs.108. It has: six Rs.10 notes, eight Rs.5 coins, and four Rs.2 coins. Working it out: (6 × Rs.10) + (8 × Rs.5) + (4 × Rs.2) = Rs.60 + Rs.40 + Rs.8 = Rs.108.
In simple words: Find the value of each coin or note type, then add them all up.

Exam Tip: Always list out each denomination and count, then multiply by the coin/note value before summing.

Question 9. How did you count the money in the arrangements? Discuss in the class.
Answer: First arrangement - Rs.80: I sorted the coins by type - four Rs.5 coins, four Rs.10 coins, and one Rs.20 coin. Then I multiplied each type's count by its value and added them: (4 × Rs.5) + (4 × Rs.10) + (1 × Rs.20) = Rs.80. Second arrangement - Rs.108: I identified six Rs.10 notes, eight Rs.5 coins, and four Rs.2 coins, then calculated (6 × Rs.10) + (8 × Rs.5) + (4 × Rs.2) = Rs.108.
In simple words: Group coins by type, find the total value of each group, and add all groups together.

Exam Tip: Organizing by denomination makes counting faster and helps avoid mistakes.

Question 10. Arrange play money of amounts 1, 2, 5, and 10 to show Rs.36, Rs.125, and Rs.183. Ask your peers to tell how much it is.
Answer: To display Rs.36 - One way: use 3 Rs.10 notes plus 6 Rs.1 coins = Rs.36. Another way: use 7 Rs.5 notes plus 1 Rs.1 coin = Rs.36. To display Rs.125 - One way: use 12 Rs.10 notes plus 1 Rs.5 note = Rs.125. Another way: use 6 Rs.10 notes plus 13 Rs.5 notes = Rs.125. To display Rs.183 - One way: use 18 Rs.10 notes plus 3 Rs.1 coins = Rs.183. Another way: use 16 Rs.10 notes plus 4 Rs.5 notes plus 3 Rs.1 coins = Rs.183.
In simple words: There are many ways to make any amount using different coins and notes. You can mix and match denominations.

Exam Tip: Always verify your combinations by adding them up to check they equal the target amount.

Question 11. Shirley and Shiv arranged their coins in the following ways. Write the number of coins in the triangles.
Answer: Looking at Shirley's arrangement on the left: the triangles should show 3, 5, 11, 17, and 7. Looking at Shiv's arrangement on the right: the triangles should show 4, 8, 12, 14, and 6. These numbers follow patterns - Shirley's are mostly odd numbers, while Shiv's are all even numbers.
In simple words: Count the coins in each group and fill in the missing numbers shown by the triangles.

Exam Tip: Look for patterns in the numbers to help predict and verify your counting.

Question 12. Describe Shiv's arrangement and write his numbers.
Answer: Shiv's coins are grouped so that each group has an even number of coins. His groups contain 4, 6, 8, 12, and 14 coins. What makes these numbers even is that they can all be split into pairs with nothing left over.
In simple words: All of Shiv's numbers are even because you can pair up the coins perfectly in each group.

Exam Tip: Even numbers always end in 0, 2, 4, 6, or 8 and can be divided equally into two groups.

Question 13. Describe Shirley's arrangement and write her numbers.
Answer: Shirley's coins are grouped so that each group has an odd number of coins. Her groups contain 1, 3, 5, 7, 11, and 17 coins. These numbers are odd because when you try to split them into pairs, you always have one coin left unpaired.
In simple words: All of Shirley's numbers are odd because each group has one coin that doesn't have a partner.

Exam Tip: Odd numbers always end in 1, 3, 5, 7, or 9 and leave one item unpaired when divided into twos.

Question 14. Shiv has arranged his numbers in pairs. We call such numbers 'even numbers'. Shirley's numbers are called 'odd numbers'. Identify numbers between 1 and 20 as even or odd. You may draw the pairing arrangement of the number.
Answer: Odd numbers between 1 and 20: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19. Even numbers between 1 and 20: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20. You can draw these by showing the pairing arrangement - even numbers form perfect pairs with no leftover, while odd numbers always have one item left without a pair.
In simple words: Even numbers can be split perfectly into pairs. Odd numbers always have one left over.

Exam Tip: Look at the last digit - if it's 0, 2, 4, 6, or 8, the number is even. If it's 1, 3, 5, 7, or 9, it's odd.

Question 15. Do you think all numbers in the times-2 table are even?
Answer: Yes, all numbers in the times-2 table are even. This is because when you multiply any number by 2, the result is always even. For example: 1 × 2 = 2 (even), 2 × 2 = 4 (even), 3 × 2 = 6 (even), and so on. Multiplying by 2 always produces numbers that can be split into pairs with nothing left over.
In simple words: Every answer in the 2 times table is even because 2 itself is even.

Exam Tip: Any number multiplied by 2 creates an even result - this is a reliable pattern to remember.

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Question 16. Circle the odd numbers and put a square around each even number. Use the crayons arrangement, if needed.
Answer: Looking at the numbers shown: Odd numbers to circle are 5, 51, 43, 37, and 69. Even numbers to put a square around are 30, 38, 52, 22, 8, and 36. You can check by looking at the last digit - odd numbers end in 1, 3, 5, 7, or 9, while even numbers end in 0, 2, 4, 6, or 8.
In simple words: Circle numbers ending in 1, 3, 5, 7, 9. Square the ones ending in 0, 2, 4, 6, 8.

Exam Tip: The quickest way is to look only at the last digit - you don't need to do any division or pairing.

Question 17. Which numbers are even and which are odd? Discuss.
Answer: Even numbers are those that can be divided by 2 without leaving a remainder. They always finish with 2, 4, 6, or 8 (or 0). Odd numbers are those that leave a remainder of 1 when divided by 2. They always finish with 1, 3, 5, 7, or 9. The simplest way to tell them apart is by looking at the last digit of the number.
In simple words: Check the last digit. If it's even-looking (0, 2, 4, 6, 8), the whole number is even. If it looks odd (1, 3, 5, 7, 9), the number is odd.

Exam Tip: Always focus on the ones place (the last digit) to classify any number quickly as even or odd.

Question 18. Shirley observes an interesting even-odd pattern in the page numbers of her Maths book. Explore your textbook and find out what Shirley has seen. Draw a square on the even numbers. Put a circle on the odd numbers.
Answer: When you look at the page numbers in a book, Shirley noticed that the numbers go even-odd-even-odd in a repeating order. Right before any odd number, there is always an even number. Right after any odd number, there is always another even number. For example, page 6 is even, page 7 is odd, and page 8 is even. This pattern happens because consecutive numbers go back and forth between even and odd.
In simple words: Odd numbers always have even numbers next to them on both sides.

Exam Tip: Look at real page numbers to verify this pattern - it's a practical way to understand how numbers alternate.

Question 19. Identify which of the following numbers are even and which are odd. Explain your reasoning.
Answer: Odd numbers: 67, 415, 99. Even numbers: 30, 46, 78, 300, 154. I identified them by checking the last digit of each number. Numbers ending in 1, 3, 5, 7, or 9 are odd, and those ending in 0, 2, 4, 6, or 8 are even. For example, 67 ends in 7 (odd), while 30 ends in 0 (even).
In simple words: Look at how each number finishes to determine if it's even or odd.

Exam Tip: Ignore all the other digits in a number and look only at the ones place to identify even or odd.

Question 20. Make two 2-digit numbers using the digits 1 and 6 without repetition.
Answer: The two 2-digit numbers made using digits 1 and 6 without repeating any digit are: 16 and 61. The number 16 is even because it ends in 6. The number 61 is odd because it ends in 1. This shows that the same digits can be arranged to make either an even or an odd number depending on which digit you place at the end.
In simple words: You can make 16 (which is even) and 61 (which is odd) using 1 and 6.

Exam Tip: To make an even number, put an even digit at the end. To make an odd number, put an odd digit at the end.

Question 21. Identify the numbers as even or odd. Now choose any two digits and make 2-digit numbers in such a way that the numbers are even.
Answer: To make 2-digit numbers that are even, you must place an even digit at the end (0, 2, 4, 6, or 8). Two possible examples are: 24 (made using digits 2 and 4) and 86 (made using digits 8 and 6). You could also make other pairs like 42 or 68 - the important thing is to ensure the last digit is always even.
In simple words: Pick any two digits, but make sure the ones place is even (0, 2, 4, 6, or 8).

Exam Tip: The second digit (ones place) decides if the whole number is even or odd - the first digit doesn't matter.

Question 22. Are there more even or odd numbers between 1 and 100?
Answer: Between 1 and 100, there are exactly 50 even numbers (2, 4, 6, ... , 100) and exactly 50 odd numbers (1, 3, 5, ... , 99). So the count of even and odd numbers is equal - neither type is more frequent than the other. They split the range exactly in half.
In simple words: There are the same number of even and odd numbers between 1 and 100.

Exam Tip: When a range is divided equally between even and odd numbers (like 1 to 100), you can verify by counting them out or by dividing the total count by 2.

Question 23. Shirley notices that both the numbers, before and after an odd number, are even. Is this true?
Answer: Yes, this is true. Odd numbers are always surrounded by even numbers. In the number sequence, even and odd numbers alternate one after the other, so any odd number will always have an even number before it and another even number after it. For example: 6 (even), 7 (odd), 8 (even). This pattern never breaks - it happens for every odd number.
In simple words: Every odd number sits between two even numbers.

Exam Tip: This pattern is part of how numbers are organized - even and odd must alternate, making it impossible for two odds or two evens to be next to each other.

Question 24. Shiv wonders if both the numbers, before and after an even number, will be odd. What do you think? Check and discuss.
Answer: Yes, this is true as well. An even number is always surrounded by odd numbers in the sequence. Because even and odd numbers take turns going down the number line, every even number must have an odd number before it and an odd number after it. For example: 5 (odd), 6 (even), 7 (odd). This is the same alternating pattern, just viewed from the opposite direction.
In simple words: Every even number sits between two odd numbers.

Exam Tip: The alternating pattern means both statements are true - evens are between odds, and odds are between evens.

Question 25. Choose any 10 numbers in order without skipping any (consecutive numbers). Write whether they are even or odd below each number. What do you notice? Discuss.
Answer: Taking 10 consecutive numbers starting with 20 and 21: 20 (even), 21 (odd), 22 (even), 23 (odd), 24 (even), 25 (odd), 26 (even), 27 (odd), 28 (even), 29 (odd). The pattern that appears is alternation - even and odd numbers keep switching back and forth. When you write out consecutive numbers in a row, you always get an even-odd-even-odd pattern that repeats without stopping. This holds true no matter which 10 numbers you pick.
In simple words: When you list numbers in order, they alternate between even and odd forever.

Exam Tip: This alternating pattern is universal and works for any set of consecutive numbers you choose to examine.