4
Q:

# 600 students took the test on physics and chemistry. 35% students failed in physics and 45% students failed in chemistry and 40% of those who passed in chemistry also passed in physics, then how many students failed in both:

 A) 162 B) 138 C) 60 D) None of these

Explanation:

Physics             Chemistry

Failed           35%                    45%

Passed         65%                    55%

Passed in both = 22% of total student

percentage of students who are passed in any of the physics or chemistry or both =(65+55) - 22 = 98%

So, the percentage of students who are failed in both = 2%

Therefore, total failed (in both subjects) students = 12

Q:

56% of 225 + 20% of 150 = ? - 109

Find the value of '?' in the above equation

 A) 264 B) 220 C) 241 D) None

Explanation:

Given 56% of 225 + 20% of 150 = ? - 109

we know that a% of b = b% of a

Now,

225% of 56 + 20% of 150 = ? - 109

200% of 56 + 25% of 56 + 20% of 150 = ? - 109

112 + 14 + 30 = ? - 109

? = 112 + 14 + 30 + 109

? = 264

7 75
Q:

5% of a number is 25% more than another number. The difference between the numbers is 96. Then find the value of the numbers?

 A) 102 & 6 B) 99 & 3 C) 104 & 8 D) 100 & 4

Explanation:

Let the first number be x and the second number be y.

Given

5% of x = (25% of y) + y

=> 5x/100 = 5y/4

=> x = 25y ......(1)

and also given that, x - y = 96

=> x = 96 + y .....(2)

From (1)&(2)

25y = 96 + y

=> 24y = 96

=> y = 4

From (1)

x = 96 + 4 = 100

Hence, the numbers are 100 & 4.

4 82
Q:

83% of 2350 = ?

 A) 1889.95 B) 1912.35 C) 1875.25 D) 1950.50

Explanation:
83% of 2350 = ?

83/100 x 2350

=8.3 x 235

=1950.50

8 119
Q:

The length of a rectangular plot is increased by 50%, to keep its area unchanged, the width of the plot should be decreased by ______?

 A) 29.87% B) 33.33% C) 22.22% D) 19.5%

Explanation:

% Decrease in Width = $\inline \fn_jvn \frac{50}{150}x100$

= 33.33%

9 239
Q:

If 15% of x = 20% of y, then x:y is  ___?

 A) 4:3 B) 5:4 C) 4:5 D) 3:4

Explanation:

Given 15% of x = 20% of y

=> 15x = 20y

=> x/y = 20/15

=> x : y = 4 : 3