Question

Marks brother is nine years older then mark. their combined ages add up to 33. how old is mark

Answer 1

Mark is 12 years old

Explanation:

a=brothers age

(9+a)+a=33

(9+12)+12

(21)+12=33

a=12

Mark is 12 years old

Answer 2

12 yrs old

Explanation:

Mark(M)+Brother(B)=33

M=B-9

therefore

(B-9)+B=33

2B-9=33

2B=33+9

2B=42

B=21

21-9=M

M=12