45 - ( n : 7 ) = 39
n : 7 = 45 - 39
n : 7 = 6
n = 6 × 7
n = 42
( n : 7 ) + 37 = 61
n : 7 = 61 - 37
n : 7 = 24
n = 24 × 7
n = 168
m : ( 42 - 37 ) = 8
m : 5 = 8
m = 8 × 5
m = 40
n × ( 56 - 49 ) = 28
n × 7 = 28
n = 28 : 7
n = 4
( m × 7 ) + 48 = 83
m × 7 = 83 - 48
m × 7 = 35
m = 35 : 7
m = 5