Question

By 1PM Shani had already shoveled 2 driveways, and by 6PM that day, the number was up to 7.

A) Find Shani's average shoveling rate, in number of driveways per hour.

B) Find Shani's shoveling rate, in hours per driveway.

Answer 1

in 5 hours , (from 1:00pm to 6:00pm), he did 5 driveways. (7-2)

so he does 1 driveway per hour
or
he takes 1 hour per driveway.

Answer 2

The number of proper subsets of set A are?

When A= {1,3,5,7}