soo i'm having trouble interpreting this question:
"Melissa is four times as old as Dan. Twenty years from now, Melissa will be twice as old as Dan then. What is Melissa's present age?"
suppose m is melissa, and d is dan
i get that m = 4d, and d remains as is.
in the second sentence, what does "Dan then" even mean here? does that mean that we won't be adding 20 there?
any help appreciated, thanks.
+36915 M=4D presently
in 20 years:
M+20 = 2(D+20)
M+20 = 2D +40
M = 2D + 20 From the first equation 1/2M = 2D Substitute this
M=1/2M + 20
1/2M = 20
M= 40 D=10
And in 20 years
M= 60 D=30
+36915 M=4D presently
in 20 years:
M+20 = 2(D+20)
M+20 = 2D +40
M = 2D + 20 From the first equation 1/2M = 2D Substitute this
M=1/2M + 20
1/2M = 20
M= 40 D=10
And in 20 years
M= 60 D=30
