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Seven years ago, my mother was seven times older than me.

In exactly eight years from now, my mother will be two times older than me.

How old is my mother now?

 Jan 20, 2021

Best Answer 

 #1
avatar+536 
+1

Say my age back then is x

So my moms back then was 7x

In 8 years, we add 15.

So 7x+15 and x+15

7x+15 is two times x+15

So 7x+15 equals 2x+30

5x=15

x=3

 

So back then your mother was 21.

 

Checking work

21+15=2(3+15)

 Jan 20, 2021
 #1
avatar+536 
+1
Best Answer

Say my age back then is x

So my moms back then was 7x

In 8 years, we add 15.

So 7x+15 and x+15

7x+15 is two times x+15

So 7x+15 equals 2x+30

5x=15

x=3

 

So back then your mother was 21.

 

Checking work

21+15=2(3+15)

MooMooooMooM Jan 20, 2021
 #3
avatar+41 
+1

I don't agree. This does not fit the question requirements.

IWantToHelp  Jan 20, 2021
 #4
avatar+41 
+1

Understood, sorry.

IWantToHelp  Jan 21, 2021
 #2
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0

(m-7) =  7(y-7)     m = mom   y = you      re-arrange to  y = 1/7 m + 6

(m+8) = 2(y+8)        or   y = 1/2 m - 4    substitute this value into the first equation

equate the two red equations       1/7 m + 6 = 1/2 m -4

                                                                10 = 5/14 m       so m = mom age now = 28        ( and you = 10 y/o)

 Jan 20, 2021

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