NCERT class 5 Math Magic chapter 2 solutions
MATH – MAGIC
Textbook in Mathematics for Class V
Lesson 2. Shapes and Angles
Practice time: – (Page 18-19)
- The angle marked in black colour is the biggest angle.
- Are the angles marked with yellow equal? _____
- Are the angles marked with green equal? _____
- Are the angles marked with blue equal? ______
- Four different angles are marked in four colours. Can you find other angles which are the same as the one marked in red? Mark them in red. Do this for other colorus.
- How many different shapes can you make by changing the angle between the matchsticks in each of these? Try.
Find out (Page 7)
Look at the sun and find out the direction from where it rises.
- From where you are, what interesting thing do you see to your east?
- Name two things that are lying to your west?
Which boat gets how much? (Page 9)
In one trip the log boat brings about 20 kg of fish. But other types of boats bring a bigger catch as given in the table. The table also shows the speed of each type of boat, which is how far each boat goes in one hour. Look at the table and calculate –
- About how much fish in all will each types of boat brings in seven trips?
Ans = Log boat = 140 kg, Long tail boat = 4,200 kg,
Motor boat = 5,600 kg, Machine boat = 42,000 kg.
- About how far can a motor boat go in six hours?
Ans = 120 km.
- If a long tail boat has to travel 60 km how long will it take?
Ans = 5 hour
|Type of boat||Cath of fish in one trip (in kg)||Speed of boat (how far it goes in one hour)|
|Log boat||20||4 km per hour|
|Long tail boat||600||12 km per hour|
|Motor boat||800||20 km per hour|
|Machine boat||6000||22 km per hour|
Practice time (Page 11-12)
- At what price per kg did Fazila sell the kingfish?
Ans = ₹ 150 per kg.
- Floramma has sold 10 kg prawns toady. How much money did she get for that?
Ans = ₹ 1500.
- Gracy sold 6 kg sword fish. Mini has earned as much money as Gracy. How many kg of sardines did Mini sell?
Ans = 9 kg.
- Basheer has ₹ 100. He spends one-fourth of the money on squid and another three-fourth on prawns.
- How many kilograms of squid did he buy?
Ans = half kilograms.
- How many kilograms of prawns did he buy?
Ans = half kilograms.
Women’s ‘Meenkar Bank’ (Page 12)
The meeting of the Meenkar Bank has just begun. Fazila is the president. Twenty fisherwomen have made their own bank. Each saves ₹ 25 every month and puts it in the bank.
- How much money does the group collect each month?
Ans = ₹ 625.
- How much money will be collected in ten years?
Ans = ₹ 6,250.
Practice time (Page 12-13)
- Gracy took a loan of ₹ 4000 to buy a net. She paid back ₹ 345 every month for one year. How much money did she pay back to the bank?
Ans = ₹ 4,140.
- Jhansi and her sister took a loan of ₹ 21,000 to buy a log boat. They paid back a total of ₹ 23,520 in one year. How much did they pay back every month?
Ans = ₹ 1,960 per month.
Questions: – (Page 14)
|Item||Price of each||Number of items||Cost|
|Bore well for fresh water||₹ 3000||1||₹ 3000|
|Bamboo rack for fish drying||₹ 2000||20||₹ 40,000|
|Cement tank||₹ 1000||4||₹ 4,000|
|Tray and knife||₹ 300||20||₹ 6,000|
|Bucket||₹ 75||20||₹ 1,500|
Total cost to set up the factory = _₹ 54,500_
When fresh fish is dried it becomes 1/3 its weight.
In one month, they plan to dry 6000 kg of fresh fish.
How much dried fish will they get in a month? _2000 kg_
Floramma – let us first calculate for 6 kg of fresh fish.
|We buy fresh fish for||₹ 15 per kg|
|We sell dried fish for||₹ 70 per kg|
We dry 6 kg fresh fish to get _2_ kg dried fish
For 6 kg fresh fish we have to pay 6 * _15_ = ₹ 90
We will sell 2 kg dried fish and get 2 * _70_ = ₹ 140
So, if we dry 6 kg fresh fish we will earn _140_ – 90 = ₹ 50.
But if we dry 6000 kg, we can earn ₹ _420_ * 1000 in one month!
Jhansi – I found that for 6000 kg fish we would need 1500 kg salt every month! Its price is ₹ 2 per kg.
- Salt 1500 * 2 = ₹ _3000_
- Packing and bus charges = ₹ 3000
So the total monthly cost of drying and selling the fish = ₹ 6,000