Answers

2014-07-03T20:44:30+05:30
Let x be mary age and y be her ssiter age
so by 1 stament x=2y
and by 2 stament x+5=y+5+2
x-y=2
so by solving eqution we get,2y-y=2 so y=2 and x=4
mary =4yrs sister =2 yrs
4 2 4
Thank u fr ur answer... Bt we want this using single variable method.
Can u help us out
Comment has been deleted
i know this method only....
  • Brainly User
2014-07-03T21:46:54+05:30
Mary is twice older than her sister. In 5 years time, she will be 2 years older than her sister find how old are they both now.

solution :
       Let present age of Mary's sister = x
           therefore Present age of Mary = y = 2x
   After 5 years ,
                 Mary's Sisters age = x+5
                 Mary's age = 2x+5
According to Question ,
                 Mary's age = Mary's Sisters age + two years

                   2x+5 = (x+5 ) + 2
                     2x+5 = x+5+2
                     2x = x+7 -5
                   2x-x = 7-5
                     x=2

hence Mary's Sister is 2 years old.
and Mary is (2x =2 *2  = 4 )4 years Old !!

Hope This helps You!!

Thank You!!

Please mark as best !!
8 4 8