37x-21x+8=200
16x+8=200
16x=200-8
16x=192
x=192:16
x=12
А) 9 + 2 3/8 = 11 3/8
б) 2 3/8 - 9 = 19/8 - 9/1 = (19-72)/8 = -53/8 = -6 5/8
в) -2 3/8 + 9 = 9 - 2 3/8 = 7 - 3/8 = 6 + (8/8 - 3/8) = 6 5/8
г) 9 - 2 3/8 = 7 - 3/8 = 6 + (8/8 - 3/8) = 6 5/8
д) - 2 3/8 - 9 = -11 3/8
е) - 9 + 2 3/8 = -7 + 3/8 = -6 5/8