Horse Magnet Boot Puzzle - with Answer

Solve the equation if you are a genius.

Answer:

First Row:
Horse = 10 + 10  10

Second Row2:
10 + (2*2)+ (2*2)

Third Row:
(2*2) -(2*1)

Fourth Row Answer:
1 + (10 *2)

Horse = 10
Magnet = 2
Boot = 1

Answer: 21