Please Help!!!!!
1) Mathew ran 3 miles in 15 minutes at a constant speed. How long will it take him to run 12 miles at the same speed?

30 mintues

60 minutes

45 minutes

50 minutes

2) Terry drove 366 miles in 6 hours at a constant speed. How long would it take him to drive 427 miles at the same speed?

3 hours

6.5 hours

7 hours

61 hours


Sagot :

You have to set these up in proportions to solve these problems. Then cross multiply and divide.

1. 3 = 15
   12 = x

3x = 15 * 12
3x = 180
x = 180 ÷ 3
x = 60

Answer: 12 miles in 60 minutes (B)

2. 366 = 6
    427 = x

366x = 427 * 6
366x = 2562
x = 2562 ÷ 366
x = 7

Answer: 427 miles in 7 hours (C)
1) you have to multiply both sides by 4.
4x3= 12. 15x4= 60.
Therefore, it will take him 60 minutes to run 12 miles.

2) Terry drives at 61 miles per hour. 427/61= 7. Therefore, it will take him 7 hours to drive 427 miles.

Hope this helps :)