Question 1196003
Today, x, the sister
e, emily


Ten years ago,
x-10, the sister
e-10, emily


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Ten years ago Emily's age was 4 times bigger than her sister's.
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{{{e-10=(x-10)+4(x-10)}}}, literally.


{{{e-10=5(x-10)}}}



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If the age of her sister is 13 today,
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{{{e-10=5(13-10)}}}

{{{e-10=15}}}

{{{e=25}}}------------Emily's age today.  


Five years from now, Emily will be 30.