NCERT Solutions for Class 4 Mathematics Math Magic for Chapter 7 Jugs And Mugs
1. The giraffe is drinking __ litres.
Ans. The giraffe is drinking 25 litres.
2. The cow is drinking __ litres.
Ans. The cow is drinking 15 litres.
3. Do you like kheer? What do you call at it home?
Ans. Yes, I like kheer. At home we call it kheer.
4. How much kheer can you have?
Ans. I can have 250 ml.
5. Can you drink 1 litre water at one time?
Ans. I cannot drink 1 litre water at one time.
6. Have you seen a one lite water bottle?
Ans. Yes, I have seen a one litre water bottle.
7. How much water does the small bottle hold?
Ans. Small bottle holds (1000/2)ml = 500 ml = 500 ml of water.
8. Then how much water does Leela’s bottle hold?
Ans. Leela’s bottle will hold = (1000/5)ml = 200 ml of water.
9. Ramu got an empty 250 ml coconut oil bottle. Look at the picture and discuss what he did to make his measuring bottle.
Ans. To make a measuring bottle: Take two empty bottles – one of large size and another of 250 ml. Fill the 250 ml bottle with water and pour the entire water into the large bottle and mark the level of 250 ml. Repeat the process again and now mark the level as 500 ml. On next repetition, the level should be marked as 750 ml. Again repeat the process and mark the level as 1 litre. Thus, we got a measuring bottle clearly marked 250 ml, 500 ml, 750 ml and 1 litre.
10. Find you own way to make a bottle which can measure 200 ml, 400 ml, 600 ml, 800 ml and 1 litre. Discuss with your friends and teacher how you made this.
Ans. To make a measuring bottle: Take two empty bottle – one of a large size and another of 200 ml. Fill the 200 ml bottle with water and pour the entire water into the large bottle and mark the level as 200 ml. Repeat the process again and now mark the level as 400 ml. Follow the same process and mark the levels as 600 ml, 800 ml and 1 litre respectively. Thus, I have obtained my measuring bottle.
11. Look at the buckets, mugs, glasses and other things in you house. Guess how much water each can hold. Check if your guess is right by using your measuring bottle.
Ans.
Guess | My Measure | |
Mug 1 | 300 ml | 250 ml |
Mug 2 | 500 ml | 500 ml |
Glass 1 | 450 ml | 500 ml |
Glass 2 | 470 ml | 500 ml |
Pot 1 | 1 litre | 1 litre |
Pot 2 | 750 ml | 750 ml |
12. Neetu has to take 3 injections in a day for 5 days. How much medicine will she need in one day? How much medicine in all for 5 days?
Ans. One injection is 5 ml.
Number of injections needed in a day = 3
Medicine injected in one day = 3 x 5 ml = 15 ml
Medicine injected in 5 days = 5 x 15 ml = 75 ml
13. How much do we use at one time?
Eye drops: We use less than 1 ml at a time
Ans. Cough Syrup: We use about 5 ml at a time.
Amla hair oil: We use about 10 ml at a time.
Shampoo: We use about 7 ml at a time.
14. List things we use more than one litre at a time.
Ans. (i) Water for watering the plants.
(ii) Water for cleaning clothes.
(iii) Water for washing a car.
(iv) Water for flashing toilet.
15. Amina’s water bottle holds one litre of water. She drank 250 ml of water and her friend Govind drank 150 ml. How much water is left in her bottle?
Ans. Total water in Amina’s bottle = 1 litre = 1000 ml
Water consumed by Amina = 250 ml
Water consumed by Govind = 150 ml
Total water consumed = 250 ml + 150 ml = 400 ml
Water left in Amina’s bottle = 1000 ml – 400 ml = 600 ml
16. Yousuf runs a tea shop. For making a glass of tea he uses 20 ml of milk. Yesterday he made 100 glasses of tea. How much milk did he use?
Ans. Milk used for making one glass of tea = 20 ml
Milk used for making 100 glasses = 100 20 ml = 2000 ml
17. Radha’s grandma was ill. The doctor gave her a bottle with 200 ml. of medicine. She has to take the medicine every morning for 10 days. How many millimetres of medicine does she have to take every morning?
Ans. Medicine contained in the bottle = 200 ml
Since the medicine is to be taken for 10 days.
Therefore, the medicine to be taken per day =200ml/10 =20 ml.
18. Total water used by them.
Ans. 30 L + 40 L + 20 L + 75 L = 165 Lites.
19. How many litres of water does your family use in a day? Guess and fill this table.
Ans.
Activity | Water used (in buckets) | Water used (in litres) |
Cooking and drinking | 3 | 45 L |
Washing clothes | 5 | 75 L |
Cleaning pots, pans | 3 | 45 L |
Bathing | 6 | 90 L |
Total water used = 45 L + 75 L + 45 L + 90 L = 255 L
20. Drops and Drops make an Ocean
(a) Is there any tap in your school or your home which is leaking?
Ans. (a) Yes, there is a tap in my school which is leaking.
(b) How much water do you think we waste through a leaking tap?
Ans. (b) About 12 litres of water is wasted through a leaking tap in a day.
(c) Place your litre jar below the leaking tap so as to catch all the drops in the bottle. After one hour check how much water is in the bottle. Find out how much water is wasted in a day?
In a weak? In a month? In a year?
Ans. On measuring the quantity of water leaked after one hour.
I found it as half litre.
Then water wasted in one day = (24 x 1/2 ) = 12 litres
In a week, wastage of water is = 12 x 7 = 84 L
In a month, wastage of water is = 12 x 30= 360 L
In a year, wastage of water is = 12 x 365 = 4380 L
21. Chelannur village has a milk society. Geetha and Ammini went there to buy 4 litres of milk. But the man could not find the one litre measure. He had only a 3 litre and a 5 litre bottle with him. But he gave them exactly 4 litres of milk. Explain how he did this.
Ans. The man first measured 5 litres and then took out 3 litres such that (5 – 3) = 2 litres of milk was given to Geetha and Ammini. The same process was repeated to get another 2 litres of milk. In this way he was able to give them exactly 4 litres of milk.