Exam 4: Formulas and Problem Solving

Solve the equation. s = 30.4 + 0.2 s

Solve the equation. x $-$ 0.07 = 0.18

20% of what number is 7.4?

Freddie leaves home and rides his bicycle out into the country for 2.7 hours. On his return trip along the same route, it takes him 0.9 of an hour longer. If his rate on the return trip was 3 miles per hour slower than on the trip out into the country, find the total roundtrip distance.

Solve the equation. $q + ( 2 q - 36 ) + ( 3 q - 18 ) = 42$

The perimeter of an equilateral triangle is 2 centimeters more than the perimeter of a square and the length of a side of the triangle is 6 centimeters more than the length of a side of the square. Find the length of a side of the equilateral triangle. (An equilateral triangle has three sides of the same length.) __________ centimeters

Solve the equation. 0.2 x + 0.7(30 $-$ x ) = 0.2(10)

Find the volume of a sphere that has a radius 12 inches long. Express the answers in terms of $\pi$ . Enter your answer without the units.

Solve the equation. x $-$ 0.15 = 0.62

An donation of $440,000 is to be divided between the YMCA and the local food bank in the ratio of 8 to 3. How much money will the YMCA receive?

Solve the following equation. Your calculator might be of some help. 9.3 x + 3.6 (557 $-$ x ) = 6,251.7

Solve i = Prt for P , if i = 24.48, r = 0.72, t = 2.

A retailer has some toe rings that cost him $2 each. He wants to sell them at a profit of 60% of the cost. What should be the selling price of the toe rings? $__________

A saltwater solution is made by dissolving 7 pounds of salt in 10 gallons of water. At this rate, how many pounds of salt are needed for 40 gallons of water?

Set up an equation and solve the following problem. How many liters of a 30% salt solution must be mixed with 10 liters of a 80% salt solution to obtain a 50% salt solution? __________ liters

Solve the equation. s = 28 + 0.3 s

A 100 milliliters of a 27% alcohol solution containts 73 milliliters of alcohol.

Suppose that the length of a radius of a circle is the same as the length of a side of a square. If the circumference of the circle is 6.84 centimeters longer than the perimeter of the square, find the length of a radius of the circle. (Use 3.14 as an approximation for $\pi$ .)

Set up an equation and solve the following problem. How many milliliters of distilled water must be added to 10 milliliters of a 70% acid solution to reduce it to a 20% acid solution? __________ milliliters

Jewelry has a very high markup rate. If a ring costs a jeweler $680, at what price should it be sold to gain a profit of 45% of the selling price?