28 + 29 + 42 = 28 + 42 + 29 = 99
Commutative property: a + b = b + a
Answer:
56
Step-by-step explanation:
Apply PEMDAS:

(-4 1/2) / (-2 2/3) =.....turn to improper fractions
(- 9/2) / (-8/3) =...when dividing fractions, flip what u r dividing by, then multiply
-9/2 * -3/8 =
27/16 =
1 11/16 <==
First add the seconds you have 45 +5+10 seconds which equals 60 seconds or 1 minutes. Now add the minutes 9 + 7 + 12 minutes = 28 minutes then add that 1 minutes that you got from the seconds 28 + 1 minute = 29 minutes 7:40 + 20 minutes = 8:00 + 9 minutes = 8:09 am. So Marsha arrived to school at 8:09 am. Comment if you have any questions.