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Sara is half her sisters age. In 20 years, she will be 3/4 her sister's age. How old is she?

1 Answer

6 votes

Answer:

40 years old

Explanation:

Let Sara be represented by P and her sister be represented by Q


p = (q)/(2) \: \: equ1


p + 20 = (3q)/(4)

From equ1, Q=2p

Substituting the value,

P+20= 3/4(2P)


p + 20 = (3(2p))/(4)

Cross multiplying,

4(P+20) = 6P

4P + 80 = 6P

Collect like terms

80 = 6P - 4P

80 = 2P

P = 80/2

P = 40

Therefore, Sara is 40 years old

User Balu Sangem
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