Click here for Detail explanation

Equation 1:

10+10+10=30

Equation 2 : 

5+5+10 =20  (from eq1 one pair shoe =10)

Equation 3:

4+4+5=13 (from eq2 man=5)

Equation 4:

5+(5+4+10)*2=?

Hint : A man wearing shoes and strap in each hand

Apply BODMAS here

5+19*2=?

5+38=43

Correct answer is 43