## Percentage

#### Percentage

1. The selling price and cost price of an article differs by 480. What is the selling price in case the profit percentage is 20%?
1. 2400
2. 2500
3. 2600
4. 2000

1. SP - CP = 480

##### Correct Option: A

SP - CP = 480
1.2x - x = 480
⇒0.2x = 480
⇒x = 2400

1. If a person sells a wooden furniture at 8% profit against 8% loss, then he could had earned Rs12 more. What is the cost price of furniture?
1. 72
2. 70
3. 80
4. 75

1. SP at Profit - SP at loss = Rs 12

##### Correct Option: D

Let Cost Price (CP) = x
Then Selling Price(SP) if he sells at profit = x(1+8%) = 1.08x
and SP, if he sells at loss = x(1-8%) = 0.92%
Given, 1.08%-0.92% = Rs12
0.16x = Rs.12
⇒x = Rs.75

1. Calculate the amount of water which should be added to 80% solution of Sulphuric acid to make it a 50% solution?
1. 60cc
2. 80cc
3. 75cc
4. 70cc

1. Assume as x be the amount of water added to make concentration of 50%

##### Correct Option: A

Concentration of Sulphuric acid = 80%
So in a 100cc, Sulphuric acid = 80cc and water = 20cc
Let x be the amount of water added to make concentration of 50%
⇒80/(100+x) = 50/100
⇒ 80/(100+x) = 1/2
∴ x = 60cc

1. An metallic alloy contains 20g copper, 20g tin and 40g silver.Then find out the percentage of tin in the alloy?
1. 20%
2. 30%
3. 25%
4. 40%

1. Percentage of silver = weight of silver/ weight of alloy

##### Correct Option: C

Total weight of alloy = 20+20+ 40 = 80g
Weight of tin = 20g
Percentage of tin = 20g/80g x 100
=25%

1. If the price of petrol is increased by 20% and subsequently by 40%. If the original price was Rs25 per litre then what is then the final price per litre?
1. 42
2. 45
3. 48
4. 40

1. Final price = Initial price x (1 + 1st increase in percent) x (1 + 2nd increase in percent)

##### Correct Option: A

Final Price = 25 x (1 + 20/100) x (1 + 40/100)
=Rs.25 x 1.2 x 1.4
= Rs. 42