Question

the ages of rahul and ravi are in ratio 5:7 four years later the sum of their ages will be 56years . what is the present age of ravi in years?

Answer 1

rahul:ravi
5:7
let rahul=5x;ravi=7x
4 years later ages
rahul=5x+4;ravi=7x+4
their sum=56
5x+4+7x+4=56
12x+8=56
12x=56-8
12x=48
x=4
ravi age=7x=7*4=28

Answer 2

Ratio of Rahul : Ravi = 5 : 7

Define x:

Let x be the constant ratio

Ratio of Rahul : Ravi = 5x : 7x

Express their age in x 4 years later

Rahul = 5x + 4

Rahui = 7x + 4

Solve x:

Their sum will be 56 years

(5x + 4) + (7x + 4) = 56

5x + 4 + 7x + 4 = 56

12x + 8 = 56

12x = 48

x = 4

Find their present age:

Rahul = 5x = 5(4) = 20

Ravi = 7x = 7(4) = 28

Answer: Rahul is 20 years old and Ravi is 28 years old.