1)
( a + b + c ) : 3 = 19, 36
a = 13, 014
b = 18
( 13, 014 + 18 + c ) : 3 = 19, 36
( 31, 014 + c ) : 3 = 19, 36
31, 014 + c = 19, 36 × 3
31, 014 + c = 58, 08
c = 58, 08 - 31, 014
c = 27, 066
2.
( a + b + c + d ) : 4 = 32, 024
a + b + c + d = 32, 024 × 4
a + b + c + d = 128, 096
3.
n × 4, 2 = 17, 02
n = 17, 02 : 4, 2
n = 4, 0523