Question

A+B=45
A:B=4 rest 5 A=? B=?

Answer 1

A:B =4
A = 4B +5

4B +5 +B =45
5B = 45 -5
5B=40
B=40:5
B = 8

A = 8x4 +5
A = 32 +5
A = 37

Answer 2

A : B = 4 r. 5 ⇒ A = 4B + 5
A + B = 45⇒ 4B + 5 + B = 45 ⇒ 5B + 5 = 45 ⇒ 5B = 45 - 5 ⇒5B = 40 ⇒ B= 8 
A = 4 x 8 + 5 = 37