4. If a and b are both positive, and a ≠ b, which of the following is a simplification of the expression above? Select one or more of the following
a2 + b2 + 1
a + b
a - b
ab
5. x = y - (50/y), where x and y are both > 0 If the value of y is doubled in the equation above, the value of x will
decrease
stay the same
increase four fold
double
increase to more than double
8. Jeff takes 20 minutes to jog around the race course one time, and 25 minutes to jog around a second time. What is his average speed in miles per hour for the whole jog if the course is 3 miles long?
6
8
10
12
14
10. A wheel has a diameter of x inches and a second wheel has a diameter of y inches. The first wheel covers a distance of d feet in 100 revolutions. How many revolutions does the second wheel make in covering d feet?