Question

The ratio of the present ages of A and B is 2 : 5. After n years, the ratio of their ages will be 1 : 2 . If the sum of
their present ages is 42 years, then find the value of n.

Answer 1

Answer:

n = 6

Step-by-step explanation:

LET , PRESENT AGE OF A BE ' X '

PRESENT AGE OF B BE 'Y '

THEIR PRESENT AGES ARE IN RATIO 2:5

X : Y = 2:5

X = 2K , Y = 5K

AFTER n YEARS ,

PRESENT OF A = X = 2K + n

PRESENT AGE OF B = Y = 5K + n

THE RATIO OF THEIR AGES WILL BE 1:2

2K + n / 5K + n = 1/2

K = n ––( 1 )

THE SUM OF THEIR PRESENT AGES IS 42

2K + 5K = 42

7K = 42

K = 6

FROM (1)

K = n = 6

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