Question

The ratio of present ages of two girls is 3:7 two years hence,the ratio of their age will be 1:2 .find their present ages.

Answer 1

let the present age of girl A = 3x

     "        "          "       " girl B = 7x

After 2 years their ages will be = 1:2

                                                    = 2(3x) : 2(7x)

by problem:

                  3x+7x = 2(3x+7x)

                     10x  = 2(10x)

                             = 20x

                       x    = 20x/10x

                             = 2

so,

the present age of girl A = 3x = 3(2) = 6yrs

"         "          "     "  girl B = 7x = 7(2) = 14yrs

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hope it helps!!