Ratio and Proportion Assessment

If x : 8 :: 3 : 4 , find x.

• 6

• 7

• 8

• 5

Answer explanation

In the given proportion, x:8::3:4, x is the unknown value. To find x, we cross multiply to get x*4 = 8*3. Solving this gives x = 6. Therefore, the correct answer is 6.

If x², 4 and 9 are in continued proportion, find x.

• 4/3

• 3/4

• 5/3

• 3/5

Answer explanation

In continued proportion, x^2, 4, and 9 means x^2/4 = 4/9. Solving for x gives x = 4/3, so the correct choice is 4/3.

Find third proportional of 9 and 15

• 25

• 15

• 30

• 20

Answer explanation

The third proportional of 9 and 15 is calculated by multiplying the two numbers and then taking the square root of the result. Therefore, the third proportional of 9 and 15 is 25.

Find mean proportional of 80 and 5

• 25

• 15

• 30

• 20

Answer explanation

The mean proportional of 80 and 5 is the square root of their product, which is sqrt(80*5) = sqrt(400) = 20. Therefore, the correct answer is 20.

Find two numbers whose mean proportional is 28 and third proportional is 224.

• 14, 56

• 10, 50

• 28,7

• 35, 42

Answer explanation

To find the numbers, we set up the proportion: x/y = y/224. Solving gives x = 14 and y = 56. Therefore, the numbers are 14 and 56.

• 7 : 5 : 7

• 21 : 30 :14

• 3 : 1 ; 1

• 2 : 1 : 3

Answer explanation

To express the ratio in simplest form, convert all mixed numbers to improper fractions. Then, find a common denominator and simplify. The ratio simplifies to 21 : 30 : 14.

• 52, 78 &  104

• 104, 78 & 52

• 108, 72 & 54

• 54, 72 & 108

Answer explanation

The correct answer is 108, 72 & 54. Divide Rs.234 in the ratio 1:2:3 to get the amounts each child receives: 108, 72 & 54.

A certain sum of money has been divided into two parts in the ratio 5 : 8. If the second part is Rs. 520, then the total amont Rs. ................

If a : b = 3 : 4 and b : c = 6 : 7, then a : b : c =

• 3 : 24 : 7

• 9 : 12 : 14

• 7 : 24 : 3

• 14 : 12 : 9

Answer explanation

To find a:b:c, multiply the ratios a:b and b:c to get a:b:c = 3*2 : 4*2 : 4*7 = 6 : 8 : 28. Simplify to get 9 : 12 : 14.

If x : 4 = 9 : 12, then x = ...........