Molly walks to Raven's house, which is 3 miles due east of her house. Then she and Raven walk to the library, which is 4 miles due north of Raven's house. Molly then walks home. If she averages walking 3 miles per hour, how long does Molly spend walking?

3 hours and twenty five minutes, i think

4 hours

Step-by-step explanation:

First we find the distance between the library and Molly's house.

The line segment from Molly's house to Raven's house, 3 miles, and the line segment from Raven's house to the library, 4 miles, form the legs of a right triangle. Using the Pythagorean theorem,

a²+b²=c²,

3²+4²=c²

9+16=c²

25=c²

Take the square root of each side:

√ (25) = √ (c²)

5 = c

This makes the total number of miles Molly walks

3+4+5 = 12 miles.

Since she travels 3 miles per hour, she travels 12/3 = 4 hours.