Randy has a lot of homework tonight. he needs to work for 45 minutes on social studies, 40 minutes on science, and 1 hour and 15 minutes on math. it will also take him 10 minutes to get ready for bed. if he wants to be in bed at 10: 00, what time does he need to start his homework?

You add up 45 and 15 to get one hour, then add the remaining 40 and 10. Then the hour. After it is all added up you will have 2hrs and 50. He would need to starts  at 7:10

Step-by-step explanation:

i dont know sorry

step-by-step explanation:

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.