Question 336107
when maria was born her mother was 24 years old. 
At maria's birth: mom = maria + 24
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at present maria's age is 20 percent of her mother age. how old is maria now
Now:  maria = 0.20(mom)
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Substitute for "mom" and solve for "maria"
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maria = 0.20(maria + 24)
maria = 0.2(maria) + 0.2(24)
0.8(maria) = 4.8
maria now  = 6 yrs old
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Cheers,
Stan H.