Can u plz help with this?

Question

The sum of the ages of Mike and Dan is 20 years. in 4 years, Dan's age will be three-fourths of Mike's age.

How old is Mike now?

Please help. =]

Answer 1

M is Mike's age, D is Dan's age

M+D=40

D+4=.75(M+4)

Now solve for D & M

First reduce the first equation to D=40-M

now substitute that into the second to get:  40-M+4=.75(M+4)

That get's you started, you should be able to solve it from here.

Answer 2

"The sum of the ages of Mike and Dan is 20 years."

M+D = 20

D = 20-M

"In 4 years"

Mike will be M+4

Dan will be D+4

"Dan's age will be three-fourths of Mike's age."

D+4 = (3/4)(M+4)

By substitution,

(20-M)+4 = (3/4)(M+4)

Solve for M:

(20-M)+4 = (3/4)(M+4)

20+4 - M = (3/4)M+3

21 = (7/4)M

M = 21×4/7 = 12

Mikey is 12 now.

Answer 3

m= mike's age

d= dan's age

m+d=20

d+4 = (3/4)(m+4)

4d + 16 = 3m + 12

4d = 3m-4

d = 3/4 m - 1

m + (3/4)m - 1 = 20

(7/4) m = 21

m= 12

d= 8

Mike is 12

Answer 4

Mike is 28 now. In four years he will be 32.

Answer 5

Are you shure you have the fact that Dan will be 3/4 of Mikes age? here is what i got

Alright, your equations are:

D= Dan's age, M=Mikes Age

1)D+M=20

2)(D+4)*.75=M+4; (D+4)*.75-4=M



Subbing 2) into 1) we get

D+(D+4)*.75-4=20

1.75D+3=24

1.75D=21

D=12

12+M=20, M=8

Check:

12+4=16

8+4=12

16/12=.75, it matches, however i am getting the ages reversed in the problem..