Ratio and Proportion Questions and Answers

Let the salaries of A, B, C be x, 2x and 3x respectively.

Then,2x + 3x = 6000 => x = 1200.

A's salary = Rs. 1200, B's salary = Rs. 2400, and Cs salary Rs. 3600.
Excess of C's salary over A's=\frac{2400}{1200}\times 100= 200%.

Video solution:

3A = 4B = 7C = k,Then A = k/3, B = k/4 and C= k/7.

A : B : C = k/3 : k/4 : k/7 = 28:21 :12.

Cs share = Rs. [427 x (12/61)] = Rs. 84

Suppose there are all the pigeons then total no of heads are 340 and total no of legs are 1060. Let us suppose number of rabbits is x and number of pigeons is y.
We know rabbit has 4 legs and pigeon has 2.
so, 1st equation will be x + y = 340
and, 2nd equation will be 4x + 2y = 1060.
solving, 1st and 2nd equation we get number of pigeons = 150

Indian stamps are common to both ratios. Multiply both ratios by factors such that the Indian stamps are represented by the same number.

US : Indian = 5 : 2, and Indian : British = 5 : 1. Multiply the first by 5, and the second by 2.

Now US : Indian = 25 : 10, and Indian : British = 10 : 2

Hence the two ratios can be combined and US : British = 25 : 2

Video solution:

Dog : Hare = (3*3) leaps of hare : 5 leaps of hare = 9 : 5.

Video solution:

Let the number of boys and girls be 8x and 5x.
As we know number of girls is 160.
We even know 5x is the ratio of girls in the college.
Therefore, 5x =160 => x = 32
Total number of students = 8x + 5x = 13x
Total number of students = 13 * 32 = 416

Video solution:

Selling price of the mixture = 70 and profit = 20%

Cost price of the mixture = 70×100/120=70×5/6
By applying alligation rule:

50(least price) 60(high price)
70 x (50/60) (new price *(least*high)
60-(175/3) : (175/3)-50

So ratio = 60−(175/3) : (175/3)-50

= 1 : 5

let the no of i10 cars be x and i20 be y
now the rejected i10 cars are 4x/100 and i20 cars are 8y/100

and it is given that 4x/100 +8y/100 = 7(x+y)/100
so we get y = 3x
so the ratio is 3:1

income ratio should be=1:2:3
expense ratio should be=3:2:1
savings of a=1/6-(1/6*3/6)=1/12
savings of b=2/6-(2/6*2/6)=2/9
savings of c=3/6-(3/6*1/6)=5/12
so,savings ratio=1/12:2/9:5/12=3/36:8/36:15/36
so,answer is c>b>a

Video solution:

Assume the present students and teachers are 30K, K
After new recruitments of students and teachers the strength becomes 30K + 50, K + 5 respectively. But given that this ratio = 25 : 1
⇒30K+50 / K+5=25 : 1⇒30K+50 / K+5=25 : 1
Solving we get K = 15
So present teachers are 15.

Video solution:

As the the ratio of their incomes are in ascending order, and their
expenses are in descending order, their savings also in their incomes order.
So savings order = A < B < C

By that time Anusha covered 100m, Bhanu covered 90m. So ratio of their speeds = 10 : 9
By that time Bhanu reached 100m, Esha covered 90m. So ratio of their speeds = 10 : 9
Ratio of the speed of all the three = 100 : 90 : 81
By that time Anusha covered 100m, Esha Covers only 81.