-2 < 4x - 10 < 6
+10. +10. +10
8 < 4x < 16
÷4. ÷4. ÷4
2 < x < 4
Here is how we get the answer....
First, replace f(x) with y . ...
Replace every x with a y and replace every y with an x .
Solve the equation from Step 2 for y . ...
Replace y with f−1(x) f − 1 ( x ) . ...
Verify your work by checking that (f∘f−1)(x)=x ( f ∘ f − 1 ) ( x ) = x and (f−1∘f)(x)=x ( f − 1 ∘ f ) ( x ) = x are both true.
The answer is approx. 10.8 per hour.
If you want to round it up, it would be 11. I prefer you not to round though as this is Money. Money should have decimals included.
Rate x time = distance
25 x 35/60 = distance (35/60 is 35 minutes out of an hour- 60 minutes)
25/1 x 7/12 = distance (I put the 25 over 1 and reduced 35/60)
175/12 ≈ 14.58 miles
Notice that the time had to be in a fraction of an hour in order to do this.
