Exam 4: Formulas and Problem Solving

Solve the equation for x . $a x + b y - c = 0$

A dirt path 1 feet wide surrounds a rectangular garden that is 25 feet long and 37 feet wide. Find the area of the dirt path. __________ square feet

Solve the equation. $30 x + 31 \left( 5 \frac { 1 } { 10 } - x \right) = 90$

Use the formula $i = P r t$ to reach a solution for the following problem. For how many years must $7,450 be invested at a 2% annual interest rate to earn $894.00? __________ years

Set up an equation and solve the following problem. Andy starts walking from point A at 1 mile per hour. One-half hour later, Aaron starts walking from point A at 6 miles per hour and follows the same route. How long (in hours) will it take Aaron to catch up with Andy? __________ hours

If 21 pounds of fertilizer will cover 1,400 square feet of lawn, how many pounds are needed for 2,800 square feet? __________ pounds

Set up an equation and solve the following problem. Andy starts walking from point A at 2 miles per hour. One-half hour later, Aaron starts walking from point A at 4 miles per hour and follows the same route. How long (in hours) will it take Aaron to catch up with Andy?

Find the length of an altitude of a trapezoid with bases of 22 inches and 16 inches and an area of 190 square inches. __________ inches

Solve the equation. 0.34 x + 0.37( x + 382) = 323.81

Use the formula $i = P r t$ to reach a solution for the following problem. How long (in years) will $7,560 need to be invested at a 7% annual interest rate to earn $2,646.00?

A car leaves a town traveling at 20 miles per hour. 7 hours later a second car leaves the town traveling the same route and overtakes the first car in 2 hours. How fast was the second car traveling?

Solve the equation. $586 ( 2 w ) = 2,344$

The equation $\frac { 3 } { 3 x + 1 } + 1 = \frac { 4 } { 4 x - 3 }$ is a proportion.

The ratio of male students to female students at a certain university is 2 to 9. If there is a total of 7,271 students, find the number of male students and the number of female students.

What is 7% of 22?

A saltwater solution is made by dissolving 2 pounds of salt in 14 gallons of water. At this rate, how many pounds of salt are needed for 70 gallons of water. __________ pounds

A percent is never greater than 100.

Tom bought an electric drill at a 5% discount sale for $25.65. What was the original price of the electric drill?

Solve the equation. $\frac { n + 7 } { n } = \frac { 8 } { 7 }$

Suppose that the length of a rectangle is 40 centimeters less than 9 times its width. The perimeter of the rectangle is 140 centimeters. Find the length and width of the rectangle.