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Mathematics Mathematics, 29.12.2020 18:30, lame3245 a grandfather is nine times older than his granddaughter. In 8 years the grandfather will be five times older than his granddaughter how old is each of them now?

1 Answer

1 vote

Answer:

Granddaughter = 8

Grandfather = 72

Explanation:

Let :

Granddaughter's age = x

Grandfather's age = y

y = 9x

Age in 8 years :

Granddaughter's age = x + 8

Grandfather's age :

y + 8 = 5(x + 8)

y = 9x

Then ;

9x + 8 = 5(x + 8)

9x + 8 = 5x + 40

9x - 5x = 40 - 8

4x = 32

x = 32 / 4

x = 8

y = 9x = 9*8 = 72

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