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Your mother is 25 years older than you. Your father is 3 years older than your mother. The product of all three ages are 32,130. How old is your father?

 Feb 23, 2021
 #1
avatar+73 
+7

Let x be our age, m be mother's age, and f be father's age. If mother is 25 years older than us, x+25=m

If father is 3 years older than mother, m+3=f

The product of all 3 ages are 32130

xmf=32130

Substitute m with x+25

m+3=f

x+25+3=f

x+28=f

Substitute now f and m:

xmf=32130

x(x+25)(x+28)=32130

(x^2+25x)(x+28)=32130

x^3+28x^2+25x^2+700x=32130

x^3 +53x^2+700x=32130

x^3+53x^2+700x-32130=0

m=25+!7

m=42

f=m+3

f=42+3

f=45

45 years old.

 

😊

 Feb 23, 2021
edited by Vanilla  Feb 23, 2021
 #2
avatar+36916 
+1

y = you

m = 25 + y

f = 25 + y + 3

 

y * (25+y) ( 25+y + 3)  = 32130

y3 + 53y2 +700y -31430 = 0                          y = 17 via wolframalpha

 

father = 17 + 28 =   45 y/o      as Vanilla found !

 Feb 23, 2021

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