SOLUTION: mary and jane are sisters born 3 years apart. six years ago, mary was twice janes age then. how old are mary and jane now?
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Question 504594: mary and jane are sisters born 3 years apart. six years ago, mary was twice janes age then. how old are mary and jane now? Answer by Maths68(1474) (Show Source):
You can put this solution on YOUR website! Let
Present age of Mary = m
Present age of Jane = j
Mary is 3 years older then Jean This is what we understand from the later part of the question, if we are right then we have to add 3 years in Jean's age then both Jean's age and Mary's age will be equal
m=j+3..............(1)
six years ago means we have to subtract 6 from their present ages
m-6=j-6
then Mary was twice Jean's age
m-6=2(j-6)
m-6=2j-12
m=2j-12+6
m=2j-6
Put the value of m from (1) to above equation
j+3=2j-6
j-2j=-6-3
-j=-9
Multiply by -1 both sides of the equation,we have
(-1)*(-j)=(-1)*(-9)
j=9
Put the value of j in (1)
m=j+3
m=9+3
m=12
Present age of Mary = m = 12 years old
Present age of Jane = j = 9 years old