Answer: He needs to start his homework at 7:10.
Explanation:
Hi, to answer this question we have to add all the times:
45 min (social studies)
40 minutes (science)
75 minutes (math) (1 hour and 15 minutes = 75 minutes)
10 minutes (to get ready)
Mathematically speaking:
45+40+75+10 = 170 minutes
If 60 minutes equals to 1 hour:
170/60 = 2.83 =
The hour is the integer part (2 hours)
The minutes is the decimal part multiplied by 60
0.83 x 60 = 50 minutes
So, 2 hours and 50 minutes, before 10:00.
10:00 -2:50 = 7:10