Question 231237: Word Problem Five - On a 570 mile trip, Andy averaged 5 mph faster for the last
240 miles than he did for the first 330 miles. The entire trip took 10 hours.
How fast did he travel for the first 330 miles? (Show a complete algebraic
solution for the problem and check the answer.
I drew a picture first.. then i thought that the mph for the first 330 miles is x? and for the second 240 miles was x+5? Im so confused on how to calculate the 10 hours part in...:(
Answer by checkley77(12844)   (Show Source):
You can put this solution on YOUR website! D=RT or T=D/R
10=330/X+240/(X+5)
10=(330*(X+5)+240X)/X(X+5)
10=(330X+1,650+240X)/(X^2+5X)
10(X^2+5X)=570X+1,650
10X^2+50X-570X-1,650=0
10X^2-520X-1,650=0
10(X^2-52X-165)=0
10(X-55)(X+3)=0
X-55=0
X=55 MPH FOR THE 330 MILE TRIP.
55+5=60 MPH FOR THE 240 MILE TRIP.
PROOF:
10=330/55+240/60
10=6+4
10=10
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