Answer:
- 3 hours
- 1 hour 45 minutes
- 300 miles
Step-by-step explanation:
1. The trains are moving toward each other at a total speed of 50 +20 = 70 miles per hour. Together, they cover the 210 mile distance in ...
time = distance/speed
time = 210 mi/(70 mi/h) = 3 h
The trains collide after 3 hours.
__
2. The fly is closing with the freight train at a speed of 100 +20 = 120 miles per hour. Together, the fly and the train cover the initial 210 mile distance in ...
(210 mi)/(120 mi/h) = 7/4 h = 1 hour 45 minutes
The fly first meets the oncoming freight train after 1 h 45 min.
__
3. The fly is flying for all three hours before the trains collide, so, at 100 miles per hour, will fly 300 miles.
the answer to your question is -12
For this problem, I believe you would just have to plug in for x.
For example, -17 divided by 10 and so on.
The answer should be C, -70. -70 divided by 10 equals -7.
First, find the lowest common denominator. That is 12. You only have to change 3/4 into 12ths.
3/4 = 9/12
11/12 – 9/12 = 2/12 = 1/6