27) 3 (-5) (-7)
When there is no math symbol between numbers it is multiplication.
Multiply from left to right:
3 * -5 = -15
-15 * -7 = 105
28) -2 * 2 (-3) *2 =
-2 *2 = -4
-4 * -3 = 12
12*2 = 24
31) A negative divided by a negative is positive:
-128 / -4 = 32
32 -36 / 2 / 24 /4
Divide the top and bottom first then divide those:
-36 / 2 = -18
24 / 4 = 6
-18 / 6 = -3