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All questions of Comparing Quantities for Class 8 Exam
A publisher offers a discount of 10% on his books and still makes a profit of 20%. What is the actual cost of a book if it is marked at Rs. 320?- a)Rs. 220
- b)Rs. 240
- c)Rs. 210
- d)Rs. 260
Correct answer is option 'B'. Can you explain this answer?
A publisher offers a discount of 10% on his books and still makes a profit of 20%. What is the actual cost of a book if it is marked at Rs. 320?
a)
Rs. 220
b)
Rs. 240
c)
Rs. 210
d)
Rs. 260
 | Shubham Sharma answered |
Here Marked Price = ₹ 320.
and Discount = 10%
Selling Price = 320 – 10% of 320
= 320 – 32 = 288
Let C.P. be ₹ x.
∴ x + 20% of x = 288
and Discount = 10%
Selling Price = 320 – 10% of 320
= 320 – 32 = 288
Let C.P. be ₹ x.
∴ x + 20% of x = 288
Mohan purchased a tape recorder and spent Rs. 66 on its repair. He sold the tape recorder for Rs. 1130 and made a profit of 24%. At what price did he buy the tape recorder?- a)Rs. 5684
- b)Rs. 5284
- c)Rs. 5784
- d)Rs. 5648
Correct answer is option 'A'. Can you explain this answer?
Mohan purchased a tape recorder and spent Rs. 66 on its repair. He sold the tape recorder for Rs. 1130 and made a profit of 24%. At what price did he buy the tape recorder?
a)
Rs. 5684
b)
Rs. 5284
c)
Rs. 5784
d)
Rs. 5648
 | Pooja Shah answered |
Let C.P. be ` x.
then (x + 66) + 24% of (x + 66) = 7130
(x+66) +
= 7130
100x + 6600 + 24x + 1584 = 713000
⇒ 124x = 713000 – 8184
⇒ 124x = 704816
x = 704816 / 124 = 5684
then (x + 66) + 24% of (x + 66) = 7130
(x+66) +
= 7130100x + 6600 + 24x + 1584 = 713000
⇒ 124x = 713000 – 8184
⇒ 124x = 704816
x = 704816 / 124 = 5684
If the simple interest on a sum of money at 5% per annum for 3 years is Rs. 1200. Then what is the compound interest on the same sum for the same period at the same rate?- a)Rs. 1261
- b)Rs. 1225
- c)Rs. 1241
- d)Rs. 1251
Correct answer is option 'A'. Can you explain this answer?
If the simple interest on a sum of money at 5% per annum for 3 years is Rs. 1200. Then what is the compound interest on the same sum for the same period at the same rate?
a)
Rs. 1261
b)
Rs. 1225
c)
Rs. 1241
d)
Rs. 1251
 | Amit Sharma answered |
Let sum = Rs. P
then
∴ C.I. = 9261 - 8000 = 1261
then
∴ C.I. = 9261 - 8000 = 1261
A businessman marks his good at 40% above the cost price and allows a discount of 25%. What is his gain percent?- a)5%
- b)10%
- c)15%
- d)20%
Correct answer is option 'A'. Can you explain this answer?
A businessman marks his good at 40% above the cost price and allows a discount of 25%. What is his gain percent?
a)
5%
b)
10%
c)
15%
d)
20%
| | Ananya Das answered |
Let the cost price be Rs. 100
Marked price = Rs. 140
Discount = 25% of 140 =
Selling price = 140 – 35 = 105
Gain Percent = 105 – 100 = 5%
Marked price = Rs. 140
Discount = 25% of 140 =
Selling price = 140 – 35 = 105
Gain Percent = 105 – 100 = 5%
If 8% VAT is included in the prices, then what is the original price of a bucket bought for Rs.180?- a)Rs. 165.60
- b)Rs. 162.66
- c)Rs. 163.66
- d)Rs. 164.66
Correct answer is option 'A'. Can you explain this answer?
If 8% VAT is included in the prices, then what is the original price of a bucket bought for Rs.180?
a)
Rs. 165.60
b)
Rs. 162.66
c)
Rs. 163.66
d)
Rs. 164.66
| | Shubham Sharma answered |
The bucket bought for Rs 180:
Calculate the VAT amount: Rs 180 x 8% = Rs 14.40.
Subtract the VAT amount from the total price: Rs 180 - Rs 14.40 = Rs 165.60.
The original price of the bucket is Rs 165.60.
What is a single discount equivalent to two successive discounts of 20% and 10%?- a)28%
- b)38%
- c)22%
- d)32%
Correct answer is option 'A'. Can you explain this answer?
What is a single discount equivalent to two successive discounts of 20% and 10%?
a)
28%
b)
38%
c)
22%
d)
32%
| | Nitish Kumar answered |
Let be assumed the m.p( marked price) of an object is
100Rs.
As per the question , After applying two successive discounts i.e.,
20% of 100= 100 - 20 = 80 Rs.
then 10% of 80 = 80 - 8 = 72 Rs.
Here, Total discount = 100 - 72
= 28 Rs
Now the discount% = 28/100 × 100
= 28% ___
___
100Rs.
As per the question , After applying two successive discounts i.e.,
20% of 100= 100 - 20 = 80 Rs.
then 10% of 80 = 80 - 8 = 72 Rs.
Here, Total discount = 100 - 72
= 28 Rs
Now the discount% = 28/100 × 100
= 28% ___
___
What sum will become Rs. 9724.05 in 2 years if the rate of interest is 10% compounded half yearly?- a)Rs. 6000
- b)Rs. 6800
- c)Rs. 7200
- d)Rs. 8000
Correct answer is option 'D'. Can you explain this answer?
What sum will become Rs. 9724.05 in 2 years if the rate of interest is 10% compounded half yearly?
a)
Rs. 6000
b)
Rs. 6800
c)
Rs. 7200
d)
Rs. 8000
 | EduRev Class 9 answered |
We know A =p
Here r = 10/2 = 5%
and n = 2 x 2 = 4
∴ 9724.05 = P
Here r = 10/2 = 5%
and n = 2 x 2 = 4
∴ 9724.05 = P
9724.05 = P 
9724.05 = P
9724.05 = P
A shopkeeper increases the price of an item by 10% and then allows a discount of 15%. How much has the customer to pay if the item was initially prieod at Rs. 1200 ?- a)Rs. 1120
- b)Rs. 1140
- c)Rs. 1122
- d)Rs. 1124
Correct answer is option 'C'. Can you explain this answer?
A shopkeeper increases the price of an item by 10% and then allows a discount of 15%. How much has the customer to pay if the item was initially prieod at Rs. 1200 ?
a)
Rs. 1120
b)
Rs. 1140
c)
Rs. 1122
d)
Rs. 1124
 | Athul Singh answered |
Price = Rs. 1200
Increased Price = 1200 + 10% of 1200
= 1200 + 120 = 1320
Discount
The net payable amount = 1320 – 198
= Rs.1122
Increased Price = 1200 + 10% of 1200
= 1200 + 120 = 1320
Discount
The net payable amount = 1320 – 198
= Rs.1122
A milkman sold two of his cows for Rs. 20000 each. On one he made a gain of 5% and on the other a loss of 10%. What is his overall gain or loss?- a)1269.84 Loss
- b)1269.84 Profit
- c)1169.84 Loss
- d)1169.84 Profit
Correct answer is option 'A'. Can you explain this answer?
A milkman sold two of his cows for Rs. 20000 each. On one he made a gain of 5% and on the other a loss of 10%. What is his overall gain or loss?
a)
1269.84 Loss
b)
1269.84 Profit
c)
1169.84 Loss
d)
1169.84 Profit
| | Chhavi Singh answered |
C.P. of 1st cow
C.P. of 2nd cow =
Total C.P. = 19047.62 + 2222.22 = Rs. 41269.84
Total S.P. = Rs. (20000 + 20000) = Rs. 40000
Overall loss = 41269.84 – 40000 = 1269.84
C.P. of 2nd cow =
Total C.P. = 19047.62 + 2222.22 = Rs. 41269.84
Total S.P. = Rs. (20000 + 20000) = Rs. 40000
Overall loss = 41269.84 – 40000 = 1269.84
What is the compound interest on Rs. 62500 for 1 1 2 years at 8% per annum compounded half yearly?- a)Rs. 7804
- b)Rs. 7004
- c)Rs. 7204
- d)Rs. 7624
Correct answer is option 'A'. Can you explain this answer?
What is the compound interest on Rs. 62500 for 1 1 2 years at 8% per annum compounded half yearly?
a)
Rs. 7804
b)
Rs. 7004
c)
Rs. 7204
d)
Rs. 7624
 | Kavya Saxena answered |
We know 
∴
∴
then C.I. = 70304 – 62500 = 7804
72% of 250 students are good in science. How many students are not good in science?- a)180
- b)70
- c)120
- d)130
Correct answer is option 'B'. Can you explain this answer?
72% of 250 students are good in science. How many students are not good in science?
a)
180
b)
70
c)
120
d)
130
 | Geetika Shah answered |
The no. of students good in science
No. of students not good in science
= 250 – 180 = 70
No. of students not good in science
= 250 – 180 = 70
Rahman bought a mobile for Rs. 3300 including a tax of 10%. What is the price of mobile before VAT was added?- a)Rs. 2500
- b)Rs. 3000
- c)Rs. 2800
- d)Rs. 400
Correct answer is option 'B'. Can you explain this answer?
Rahman bought a mobile for Rs. 3300 including a tax of 10%. What is the price of mobile before VAT was added?
a)
Rs. 2500
b)
Rs. 3000
c)
Rs. 2800
d)
Rs. 400
| | Geetika Shah answered |
Let the price of mobile before VAT be ₹ x.
∴ x + 10% of x = 3300
∴ x + 10% of x = 3300
By selling 20 pens a shopkeeper gains equal to the selling price of 4 pens. What is his gain percent?- a)15%
- b)20%
- c)25%
- d)30%
Correct answer is option 'C'. Can you explain this answer?
By selling 20 pens a shopkeeper gains equal to the selling price of 4 pens. What is his gain percent?
a)
15%
b)
20%
c)
25%
d)
30%
| | Pooja Shah answered |
Let selling price of 20 pens = Rs. 20
∴ Now Gain = Rs. 4
Cost Price = 20 – 4 = 16
Hence Gain percent 4/16 x 100 = 25%
∴ Now Gain = Rs. 4
Cost Price = 20 – 4 = 16
Hence Gain percent 4/16 x 100 = 25%
Calculate the compound interest on Rs. 10000 at 10% per annum for 3 years, if interest compounded annually?- a)Rs. 3130
- b)Rs. 1331
- c)Rs. 3310
- d)Rs. 13310
Correct answer is option 'C'. Can you explain this answer?
Calculate the compound interest on Rs. 10000 at 10% per annum for 3 years, if interest compounded annually?
a)
Rs. 3130
b)
Rs. 1331
c)
Rs. 3310
d)
Rs. 13310
| | Nandini Sarkar answered |
Here
∴ C.I. = A P = 13310 - 10000
= Rs. 3310
∴ C.I. = A P = 13310 - 10000
= Rs. 3310
The cost of a mobile phone is Rs. 3000. A gain of 10% should be made after a discount of 20%. What is the marked price of the mobile phone?- a)Rs. 4000
- b)Rs. 4125
- c)Rs. 4025
- d)Rs. 4100
Correct answer is option 'B'. Can you explain this answer?
The cost of a mobile phone is Rs. 3000. A gain of 10% should be made after a discount of 20%. What is the marked price of the mobile phone?
a)
Rs. 4000
b)
Rs. 4125
c)
Rs. 4025
d)
Rs. 4100
| | Aditya Chatterjee answered |
Selling Price = 3000 × 11/1000 = 3300
Let Marked Price be ` x
x - 20% of x = x -
Let Marked Price be ` x
x - 20% of x = x -
The value of a machine at the rate of 20% per annum. It was purchased 2 years ago if its present value is Rs. 4000, for how much was it purchased?- a)Rs. 62500
- b)Rs. 62800
- c)Rs. 65200
- d). 56500
Correct answer is option 'A'. Can you explain this answer?
The value of a machine at the rate of 20% per annum. It was purchased 2 years ago if its present value is Rs. 4000, for how much was it purchased?
a)
Rs. 62500
b)
Rs. 62800
c)
Rs. 65200
d)
. 56500
 | Rahul Rane answered |
Let value of a machine 2 years ago, = P
Present value of machine = Rs.40000
Time, n = 2 years
Rate of depreciates, R = 20% per annum
Now,
Amount (A) = P (1 + R/100)^n [Where, A = Amount with compound interest
P = Present value
R = Annual interest rate
n = Time in years]
∴ Value = P (1 - R/100)n [∵ Rate decreases]
⇒ 40000 = P (1 - 20/100)2
⇒ 40000 = P (1 - 1/5)2
⇒ 40000 = P (4/5)2
⇒ 40000 = P � 16/25
⇒ P = 40000 x 25/16
⇒ P = 2500 x 25
⇒ P = 62500
∴ Value of a machine 2 years ago is Rs.62500.
What is the rate percent per annum if Rs. 2000 amount to Rs. 2662 in 
years, it interest being compounded half yearly?- a)20%
- b)10%
- c)25%
- d)16%
Correct answer is option 'B'. Can you explain this answer?
What is the rate percent per annum if Rs. 2000 amount to Rs. 2662 in years, it interest being compounded half yearly?
years, it interest being compounded half yearly?a)
20%
b)
10%
c)
25%
d)
16%
 | Hrishikesh Kulkarni answered |
The correct answer is a.
Given,
Given,
Principal = Rs.2000
Amount = Rs.2662
If the S.P. of 10 articles is equal to the C.P. of 11 articles. What is the gain percent?f- a)5%
- b)10%
- c)15%
- d)20%
Correct answer is option 'B'. Can you explain this answer?
If the S.P. of 10 articles is equal to the C.P. of 11 articles. What is the gain percent?f
a)
5%
b)
10%
c)
15%
d)
20%
 | Samridhi Banerjee answered |
SP of 10 articles = CP of 11 articles
let CP of 1 article be Rs. 1
CP of 10 articles = Rs. 10
SP of 10 articles = CP of 11 articles = Rs. 11
SP is greater than CP
Profit = SP - CP = 11-10 = Rs. 1
Profit % = Profit/CP � 100
= 1/10�100 = 10%
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