Solving Equations
More Solving Equations
Percent
Rates & Ratios
Proportions
100
Solve these equations. d - 17 = 4 -5 + r = 8
d = 21 x = 13
100
Solve. 6.3 = 2x - 4.5
6.3 = 2x - 4.5 +4.5 +4.5 10.8 = 2x /2 /2 5.4 = x
100
Write as a decimal. 24% 173%
.24 1.73
100
Find the unit rate. Doug makes $43.45 in 5.5 hours.
$43.45 / 5.5 = $7.9/hour
100
Solve this proportion. 4/(y+2) = 10/25
100 = 10y +20 -20 -20 80 = 10y /10 /10 8 = y
200
Solve these equations. d/2 = 9 -50 = 10y
d = 18 -5 = y
200
Solve. 5/8 = 2m + 3/8
5/8 = 2m + 3/8 -3/8 -3/8 2/8 = 2m /2 /2 1/8 = m
200
22.5 is 45% of what number?
22.5/x = 45/100 2250 = 45x 50 = x
200
A cell phone company found that 15 of their phones sold in June were defective. The company sold 250 phones in June. How many of the 300 phones sold in July should they expect to be defective?
15/250 = x/300 4500 = 250x /250 /250 18 = x 18 of the 300 phones sold in July will be defective.
200
Solve this proportion. (y+2)/(y+7) = 11/31
31y + 62 = 11y + 77 -11y -11y 20y + 62 = 77 -62 -62 20y = 15 /20 /20 y = 3/4
300
Anna shipped a package that cost $1.15. It weighed 5 ounces. Write and solve an equation to determine the shipping cost per ounce.
1.15 = 5x /5 /5 23 = x $.23 per ounce
300
Solve. 2(c+3) = c - 13
2(c+3) = c - 13 2c + 6 = c - 13 -c -c c + 6 = -13 -6 -6 c = -19
300
Write each as a percent and a fraction. .17 .185
17/100 , 17% 37/200, 18.5%
300
Four pounds of apples cost $1.96. How much for 13 pounds?
1.96 / 4 = $.49/lb .49 * 13 = $6.37 for 13 pounds
300
Triangle ABC ~ Triangle DEF Side length BC = 4cm Side length CA = 8cm Side length EF = 2cm Side length FD = x Solve for x. Draw the triangles and label to determine.
x/8 = 2/4 4x = 16 /4 /4 x = 4 Side FD is 4cm long.
400
Write and solve an equation to represent "The product of 9 and a number is -72"
9x = -72 /9 /9 x = -8
400
Solve for the variable indicated. 3m -7n = p ; solve for m
3m -7n = p ; solve for m 3m -7n = p +7n +7n 3m = p+7n /3 /3 m = (p+7n)/3
400
Use the formula I = Prt to find the simple interest for 3 years on a $2500 loan at 7.5% rate each year.
I = (2500) * (.075) * (3) I = (187.5) * (3) I = 562.50 $562.50
400
The ratio of freshmen to sophomores in a drama class is 4:7. If there are 21 sophomores, how many freshmen are in the drama class?
4/7 = x/21 84 = 7x /7 /7 12 = x There are 12 freshmen in the drama class.
400
David is 5 feet tall and casts a shadow of 12 feet. A nearby tree is 46 feet tall. How long of a shadow will it cast?
5/12 = 46/x 5x = 552 /5 /5 x = 110.4 feet long
500
Solve. x - 4 + 2x = 14
3x - 4 = 14 +4 +4 3x = 18 /3 /3 x = 6
500
The formula c = 5p +215 relates c, the cost in dollars of hosting a birthday party at a skating rink to p, the number of people attending. a) Solve for p b) If Allie's parents are going to spend $300 for a party, how many people can attend?
a) c = 5p + 215 -215 -215 c - 215 = 5p /5 /5 (c-215)/5 =p b) (300-215) / 5 = p 85 / 5 = p 17 = p 17 people can attend Allie's party if her parents are willing to spend $300.
500
A local bookstore sells a cook book for the retail price of $35.00. An online retailer sells it for 37% off the retail price, but there is 7% tax before shipping and you must pay $4.99 for shipping. How much would the book cost from the online retailer? (Round tax to nearest cent)
35 * .37 = 12.95 $12.95 off retail price 37-12.95 = 24.05 (price before tax) 24.05 * .07 = 1.68 24.05 + 1.68 + 4.99 = 30.72 The book will cost $30.72 from the online retailer.
500
A map of Indiana is being made to a scale of 1/2in:20miles. Indianapolis is 128 miles from Fort Wayne. How many inches apart will the two be on the map?
.5/20 = x/128 64 = 20x /20 /20 3.2 = x The two will be 3.2 inches apart on the map.
500
A building is 50 feet tall and casts a shadow of 70 feet. A nearby flagpole casts a shadow of 28 feet. How tall is the flagpole?
50/70 = x/28 1400 = 70x /70 /70 20 = x The flagpole is 20 feet tall.
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