Did you mean "If Kurt was 10 years older" ?
The way you have it, Kurt is 10, his sister would have to be 5, but then their combined ages can't be 36
If as I think it should be,
let Kurt's present age be x
let his sister's present age by y
in 10 years ...
Kurt = x+10
sister = y +10
we are told that Kurt is twice her age at that time ...
x+10 = 2(y+10)
x = 2y + 10
also x+10 + y+10 = 36
x + y = 16
sub in x = 2y+10
2y+10 + y = 16
3y = 6
y = 2 , then x = 14
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If Kurt were 10 years old, he would be twise as old as his sister, and their combine ages would be 36. How old are Kurt and his sister?
1 answer