Question 1119162
a woman is older than her daughter by 15 yrs,
w = d + 15
 10 yrs ago the ratio of their age was 4:1
{{{(w-10)/(d-10)}}} = {{{4/1}}}
Cross multiply
w - 10 = 4(d-10)
w - 10 = 4d - 40
w = 4d - 40 + 10
w = 4x - 30
Replace w with (d+25) from the first statement
d + 15 = 4d - 30
d - 4d = -30 -15
-3d = -45
d = -15/-3
d = +15 is the daughter's age
find w
w = 15 + 15
w = 30 is the woman's age
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:
Check by finding the ratio of their ages 10 ears ago: 20:5 = 4:1