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2 years ago

Ama's age is two thirds that of her elder sister. Four years ago ama's age was half the sister's. How old is the sister?

Mathematics

2 answers:

Westkost [7]2 years ago

8 0

Answer:

Step-by-step explanation:

Ama's sister is 12 now and Ama is 8. 8/12 simplified is 2/3.

Four years ago Ama's would have been 4 and her sister would have been 8. 4/8 simplified is 1/2.

The equations:

(Ama is a)

(Ama's sister is s)

a = (2/3)s

a - 4 = (1/2)(s - 4)

Step one:

You would substitute the first equation into the second equation to get

(2/3)s - 4 = (1/2)(s - 4)

Step two:

Multiply by 6 to get rid of the fractions to get

4s - 24 = 3(s - 4)

Step three:

Simplify to get

4s - 24 = 3s - 12

Step four:

Subtract 3s and add 24 to get

s = 12

Step five:

Input the s value into the first equation to get

a = (2/3)(12) = 8

If this helped please rate, thanks, and mark brainliest! Also, please comment if it's correct :)

egoroff_w [7]2 years ago

4 0

Step-by-step explanation:

let ama's age be x

and ama's sister be y

according to question

3x=2y --------(1)

x-4=(y-4)/2 ---------(2)

after solving equation (1) and (2)

we get ama's age is 8 years and AMA'S SISTER AGE IS 12 years

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