Liz Z. answered 09/16/20
Middle school - College math tutor. I love math, and you can too!
We know distance=rate(time), or d=rt. Let person 1 travel distance 1 and bike at rate b: d1 = b(1.5 hours), or d1=1.5b.
Let person 2, who's faster, bike at rate (b+4). For this person, d2 = (b+4)(1.5 hrs), or d2=1.5b+6 after distributing 1.5.
We know that d1 + d2 = 60 km. Let's add the two equations and set them equal to 60.
d1=1.5b
+
d2=1.5b+6
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d1+d2 = 3b+6. Since d1+d2=60, substitute that:
60 = 3b + 6
Subtract 6 from each side to get 54 = 3b, and divide both sides by 3 to get b=18.
Remember b is the rate, so Wade, who was riding more slowly, rode at 18 km/hr. Randy rides 4 km/hr faster, so that's 22 km/hr.