contestada

A girl drove her bike at the rate of 10 moh and then after a flat tire she walked at the rate of 2 mph. The entire trip took 2 hours for a total of 16 miles. How long did she walk, and how long did she bike?

Respuesta :

DeanR
Let b be the biking time in hours

Let w be the walking time in hours

The entire trip took 2 hours

[tex]b + w = 2[/tex]

for a total of 16 miles

If we've biked b hours at 10 miles per hour, then we must have biked 10b miles.  Similarly for walking.

[tex]10b + 2w = 16[/tex]

[tex]2b + 2w = 4[/tex]

Subtracting,

[tex]8b = 12[/tex]

[tex]b = \frac 3 2 [/tex] hours

[tex]w = 2-b = \frac 1 2[/tex] hours

Biked 90 minutes, walked 30 minutes.

Otras preguntas