#8: 14.95+7.55=22.50 so the cost of the DVD is $22.50 and the subtraction equation is, 22.50-7.55=14.95
#10: 2/3+1/3=1 so m=1
#12: 7/9+1/3=10/9 or 1 1/9
We'll be looking for time here.
s=d/t
ts=d
t=d/s
------------------------
Average speed is:
s=(55m)/h
Distance is:
200m
---------------------------
t=(200m)/(55m/h)
t=(200m/1)*(h/(55m))
t=200/55*h
t≈3.64 hours
We know that:

Then:

Therefore:

Simplifying the above result we get:

Answer:
Answer: 2/3 (two thirds)
Explanation: Divide both denominator and numerator by the common factor of fourteen