a) [(4 * m + 5) : 3 + 10] : 5 + 5 = 10
[(4m + 5) : 3 + 10] : 5 = 10 - 5
(4m + 5) : 3 + 10 = 5 * 5
(4m + 5) : 3 = 25 - 10
4m + 5 = 15 * 3
4m = 45 - 5
m = 40 : 4
m = 10
b) [(13 + 12 * m) * 10 - 330] : 100 = 13
(13 + 12m) * 10 - 330 = 13 * 100
(13 + 12m) * 10 = 1300 + 330
13 + 12m = 1630 : 10
12m = 163 - 13
m = 150 : 12
m = 12,5