Ratio and Proportion - Quantitative Aptitude Questions Page-3

17) What is the ratio of the circumference of a circle to its radius?
(A) π
(B) π/2
(C) 2πr
(D) 2π

18) There are two numbers and their ratio is 3 : 9. If we substract 9 from both numbers then their ratio becomes 12 : 13, what is the largest number?
(A) 23
(B) 55
(C) 33
(D) 45

19) The ratio of the number of boys and girls in a school is 5 : 3. If there are 800 boys in the school, find the number of girls.
(A) 160
(B) 320
(C) 380
(D) 480

20) A shopowner blends three types of coffees. A, B and C in the ratio 3 : 5 : 7. Given that type A coffee costs Rs. 70 per kg, type B coffee costs Rs. 100 per kg and type C coffee costs Rs. 120 per kg. Calculate the cost per kg of the blended mixture.
(A) Rs. 109.3
(B) Rs. 107.3
(C) Rs. 105.3
(D) Rs. 103.3

21) The sum of two numbers is 75 and their ratio is 3 : 2. Find the numbers.
(A) 55 and 20
(B) 45 and 30
(C) 30 and 45
(D) 40 and 35

22) In a cage containing 50 parrots, 10 are blue, 18 are green, and 22 are yellow. How many green parrots should be added to make the ratio between green and yellow parrots as 3 : 2?
(A) 10
(B) 33
(C) 40
(D) 15

23) A is younger than B by 3 years. If the ratio of their current ages is 4 : 5, find the age of A?
(A) 10
(B) 13
(C) 12
(D) 15

24) If 40% of a number is equal to two-third of another number, what is the ratio of first number to the second number.
(A) 6:3
(B) 5:9
(C) 4:7
(D) 5:3