55mph.
you can solve it using the equation distance=speed x time
your total distance is 714, and you have 2 trains, one traveling some speed, x, and one traveling x+8, both traveling for 7 hours.
your equation would look like this

and you can then solve for x, which would be 47. this is the speed of the slower train, but 47+8=55 with give you the speed of the faster train.
B I’m guessing, never really worked with something like this before though
Answer: A and C
Ecplanation: photo
84/3=28
The 3 consecutive numbers would be 26,28,and 30
For the answer to the question above,
The expected value in percentage format is 0.2 x 15+0.4 x 20 + 0.3 x 30 + 0.1*35 = <u><em>23.5%</em></u>
The answer is <u><em>23.5%
</em></u>
I hope my answer helped you. Have a nice day ahead!
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