Răspuns :
27 - ( n × 24 + 1 ) ÷ 7 = 20
( n × 24 + 1 ) ÷ 7 = 27 - 20
( n × 24 + 1 ) ÷ 7 = 7
n × 24 + 1 = 7 × 7
n × 24 + 1 = 49
n × 24 = 49 - 1
n × 24 = 48
n = 48 ÷ 24
n = 2
27-(nx24+1):7=20
-(nx24+1):7 = 20-27 = -7
-nx24-1 = -7x7 = -49
nx24 = 49-1 = 48
n = 48:24 = 2