Answer:9/305
Step-by-step explanation:
Isolate the variable by dividing each side by factors that don't contain the variable.
Exact Form:
x=9/305
Decimal Form:
x
=0.02950819
Let S = his average speed.
Let D = distance traveled one way
Time = distance / speed
Set up an equation:
d/6 + d/12 = 2d/S
Multiply the equation by 12s:
12s(d/6) + 12s(d/12) = 12s(2d/s)
Simplify to get:
2sd + sd = 24d
Combine like terms:
3sd = 24d
Divide both sides by d:
3s = 24
Divide both sides by 3:
s = 24/3
s = 8
His average speed was 8 mph.
I think the common denominator is 90. 8,9,and 10 can all go into 90.
Step-by-step explanation:
Hope the above solution helps