when you add marco, ken, and amy's numbers, you get 207. kens number is 9 more than marcos. amy's number is 3 less than kens. what is amy's number?

Question

when you add marco, ken, and amy's numbers, you get 207. kens number is 9 more than marcos. amy's number is 3 less than kens. what is amy's number?

Answer 1

1)  M+K+A = 207

2)  K = M+9

3)  A = K-3

 

substitute equation 2 into equation 1:

M + (M+9) + A = 207

 

From equation 3:

A = K-3 = M+9-3 = M+6

 

Substitute that into new equation

 

M + (M+9) + (M+6) = 207

3M + 15 = 207

3M = 192

M = 192/3

M = 64

 

K = M+9 = 73

 

A = K-3 = 70