Worksheet Solutions: The Junk Seller - 2 | Mathematics for Class 4: NCERT PDF Download

Q1: Choose the correct answer from the options given below.

(i) If 9 times 2 is 18, 9 times 20 is _______
(a) 18
(b) 180
(c) 1800
Ans: (b)
If 9 times 2 is 18, then 9 times 20 is "180" because you multiply both numbers by the same factor, which is 9.

(ii) 4 x 81 is _____ more than 4 x 80.
(a) 2
(b) 4
(c) 8
Ans: (b)
4 times 81 is "4" more than 4 times 80 because 81 is 1 more than 80.

(iii) If a person who runs a tea stall earns Rs 30 in a day, how much will he earn in 10 days?
(a) 40
(b) 300
(c) 3000
Ans: (b)
If a person earns Rs 30 in a day, they will earn "300" in 10 days because you multiply the daily earnings by the number of days.

(iv) 20 x 300 =_____
(a) 60
(b) 600
(c) 6000
Ans: (c)
20 multiplied by 300 equals "6000" because you multiply the two numbers together.

(v) If 1 kg newspaper costs Rs 5, find the cost of 30 kg newspaper.
(a) 15
(b) 150
(c) 35
Ans: (b)
If 1 kg of newspaper costs Rs 5, the cost of 30 kg of newspaper is "150" because you multiply 5 by 30.

Q2: Answer the following Questions.

(i) Hariya took a loan of Rs 300 from a bank for six months. He has to pay Rs 51 every month to the bank. Babu took a loan of Rs 300. After six months; he has to pay Rs 360. Who has to pay back more?
Ans: Amount paid back by Hariya for six months = 6 x 51 = Rs 306
Amount paid back by Babu after six months = Rs 360
Since 360 is greater than 306, Babu has to pay back more.

(ii) I bought 1 kg newspaper for Rs 5, but sold it for Rs 6. How much money did I earn by selling 152 kg of newspaper?
Ans: Buying price of 1 kg Newspaper = Rs 5
Buying price of 152 kg Newspaper = 152 x 5 = Rs 760
Selling price of 1 kg Newspaper = Rs 6
Selling price of 152 kg Newspaper = 152 x 6 = Rs 912
Earnings = 912 – 760 = 152

(iii) The rate of 1 kg plastic is Rs 12. Find the cost of 63 kg plastic?
Ans: Rate of 1 kg plastic = Rs 12
Cost of 63 kg plastic = 63 x 12 = Rs 756

(iv) Anu took a loan of Rs 24000 from a bank to buy a laptop. She has to pay Rs 2250 for every month for 1 year. How much amount he will pay after 1 year?
Ans: Amount paid back in one month = Rs 2250
Amount paid back after 1 year = 2250 x 12 = Rs 27000

(v) If Rahul drinks 8 glasses of water in a day, how much water he will drink in one week?
Ans: Amount of water that Rahul drinks everyday = 8 glasses
Amount of water he will drink in one week = 8 x 7 = 56 glasses

(vi) If the cost of 1 kg Newspaper is Rs 5 and 1 kg Waste paper is Rs 4, find the cost of 42 kg newspaper and 23 kg of waste paper.
Ans: Cost of 1 kg Newspaper = Rs 5
Cost of 42 kg Newspaper = 42 x 5 = Rs 210
Cost of 1 kg waste paper = Rs 4
Cost of 23 kg waste paper = 23 x 4 = Rs 92

(vii) Kiran buys 1 kg iron for Rs 12, but sells it for Rs 14. How much does she earn when she sells 32 kg iron?
Ans: Buying price of 1 kg Iron = Rs 12
Buying price of 32 kg Iron = 32 x 12 = Rs 384
Selling price of 1 kg Iron = Rs 14
Selling price of 32 kg Iron = 32 x 14 = Rs 448
Earnings = 448 – 384 = Rs 64

(viii) If the cost of 10 kg Brass is Rs 1800, find the cost of 7 kg Brass?
Ans: Cost of 10 kg Brass = Rs 1800
Cost of 1 kg Brass = 1800/10 = Rs 180
Cost of 7 kg of Brass = 180 x 7 = 1260

(ix) Niya deposits Rs 325 every day in a savings account. How much amount he will get back after 30 days?
Ans: Amount deposited every day = Rs 325
Amount he will get back after 30 days = 325 x 30 = Rs 9750

(x) The cost of 10 pens is Rs 55. Find the cost of 1 pen?
Ans: Cost of 10 pens = Rs 55
Cost of 1 pen = 55 /10 = 5.5 = 5rupees 50 paise