21
Q:

# From a salary of an officer, 10% is deducted as house rent, 15% of the rest he spend on children's education and 10% of the balance he spends on clothes. Then, he is left with Rs. 4131. Find his total salary?

Q:

There are 1650 students in a college. The difference between the number of boys and girls in the college is 400. What is the percentage of girls in the college ?

 A) 49 B) 34 C) 43 D) 38

Explanation:

Let no. of boys be 'B' and no. of girls be 'G'

Here from given data,

B + G = 1650 .....(1)

B - G = 400 .....(2)

From (1) & (2), we get

2B = 2050

=> B = 1025

=> G = 1650 - 1025 = 625

Hence, the % of girls = 625 x 100/1650

=> 38% (approx).

2 50
Q:

What will come in place of the question mark(?) in the following question ?

56% of 870 + 82% of 180 = 32% of 90 + ?

 A) 777 B) 666 C) 606 D) 789

Explanation:

56% of 870 = 56x870/100 = 487.20

82% of 180 = 82x180/100 = 147.60

32% of 90 = 32x90/100

487.20 + 147.6 - 28.8  =  ?

? = 634.8  - 28.8

? = 606.

3 32
Q:

The price of a car is increased by 25%, by how much percent, must the new price of this car be decreased to restore its original price ?

 A) 20% B) 24% C) 21% D) 25%

Explanation:

Suppose that the original price of the car = Rs. x

Then new price of the car

=> (x) + (×25/100) Rs. 5x/

To restore the original price, the new price must be decreased by

5x/− x/4

So required percentage =(x/4)/(5x/4) × 100%

= 20%

5 102
Q:

Prasanna invested certain amount in three different schemes X, Y and Z with the rate of interest 10% p.a, 12% p.a and 15% p.a respectively. If the total interest accrued in one year was Rs. 3200 and the amount invested in Scheme Z was 150% of the amount invested in Scheme X and 240% of the amount invested in Scheme Y, what was the amount invested in Scheme Y by Prasanna ?

 A) Rs.6000 B) Rs.4500 C) Rs.7500 D) Rs.5000

Explanation:

Let a, b and c be the amounts invested in schemes X, Y and Z respectively. Then,

As we know:

Simple interest (S.I.) = PTR/100

(a × 10 × 1/100) + (b × 12 × 1/100) + (c × 15 × 1/100) = 3200

= 10a + 12b + 15c = 320000 .........(1)

Now, c = 240% of b = 12b/5 .........(2)

And, c = 150% of a = 3a/2 => a = 2/3 c = (2 × 12)b/(3 × 5) = 8b/5 .......(3)

From (1), (2) and (3), we have

16b + 12b + 36b = 320000 => 64b = 320000 => b = 5000

∴ Sum invested in Scheme Y = Rs.5000.

3 55
Q:

A man reduces his travelling time by a fraction of 2/5, as a result the distance covered by the man is increased by 20%, find the percentage increase in the speed of the man ?

 A) 77% B) 88% C) 100% D) 99%