Question 1021110
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x+y=90
y=90-x
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20x+10y=1300
20x+10(90-x)=1300
20x+900-10x=1300
10x=400
x=40
ANSWER: You spent 40 minutes biking
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CHECK:
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y=90-x=90-40=50 . You spent 50 minutes walking.
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20x+10y=1300
20(40)+10(50)=1300
800+500=1300
1300=1300
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