To solve for the total price:
1.075(50) = 53.75
She will have to pay $53.75 in total.
 
        
             
        
        
        
11/7
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100, because, x^2 - 20x + 100 = ( x - 10 )^2;
        
             
        
        
        
Answer:
   40 mph
Step-by-step explanation:
We assume "outbound" refers to the trip <em>to the lake</em>. The ratio of speeds is inversely proportional to the ratio of times, so ...
   outbound speed : inbound speed = 4 : 3
These differ by one ratio unit, so that one ratio unit corresponds to the speed difference of 10 mph. Then the 4 ratio units of outbound speed will correspond to ...
   4×10 mph = 40 mph
Paul's average speed on the outbound trip was 40 mph.
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The distance to the lake was 120 mi.