Writing and Evaluating Multiplication Equations

A multiplication equation is an equation like 2x = 10 because the variable x is multiplied by 2. Multiplication and division are inverse operations. To solve a multiplication equation, use division.

Division Property of Equality If you divide each side of an equation by the same nonzero number, the two sides remain equal.

4y = 12 y = 3 2n = 16 n = 8 12.8 = 3.2d d = 4 4/5k = 12 k = 15 3r = 42 r = 14 4c = 48 c = 12 4n = 9 n = 2¼ or 2.25

12 = 1.5w w = 8 3.5m = 14.7 m = 4.2 32 = 3.2c c = 10 2/5w = 40 w = 100 3/5 = 2/3t t = 9/10 23.8 = 3.5b b = 6.8 3/4g = 5/8 g =5/6

Anne runs 6 laps on a track. She runs a total of 1 mile, or 5,280 feet Anne runs 6 laps on a track. She runs a total of 1 mile, or 5,280 feet. Write and solve an equation to find the distance, in feet, that she runs in each lap. 6d = 5,280 d = 880 DeShawnn uses ¾ of a box of rice to cook dinner. The portion he uses weighs 12 ounces. Write and solve an equation to find the weight of the full box of rice. ¾ w = 12 w = 16

In 2004, Pen Hadow and Simon Murray walked 696 miles to the South Pole In 2004, Pen Hadow and Simon Murray walked 696 miles to the South Pole. The trip took 58 days . Suppose they traveled the same distance ach day. Write and solve a multiplication equation to find about how many miles they traveled each day. 696m = 58 m = 12 Matthew is downloading ringtones. The cost to download each ringtone is $2. When Matthew is finished he has spent a total of $10. Write and solve an equation to find the total number ringtones Matthew purchased. 2r = 10 r = 5

Writing and Evaluating Division Equations

A division equation is an equation like a/4 = 5 because the variable a is being divided by 4. Multiplication and division are inverse operations. To solve division equations use multiplication.

Multiplication Property of Equality If you multiply each side of an equation by the same nonzero number, the two sides remain equal.

z/6 = 9 z = 54 d/4 = 5 d = 20 11 = n/2.4 n = 26.4 z/16 = 8 z = 128 a/14 = 6.8 a = 95.2 x/7 = 0 x = 0 n/2.5 = 9 n = 22.5

17 = w/6 w = 102 4.7 = g/3.2 g = 15.04 d/ 5 = 10 d = 50 w/6 = 15 w = 90 t/10 = 120 t = 12 9 = c/30 c = 270 7 = d/14 d = 98

Kerry and Tya are sharing a pack of stickers Kerry and Tya are sharing a pack of stickers. Each girl gets 11 stickers. Write and solve a division equation to find how many total stickers there are s/11 = 2 s = 22 Chen is buying a ham. He wants to divide it into 6.5-ponce servings for 12 people. Write and solve an equation to find what size ham Chen should buy. h/6.5 = 12 h = 78

At the end of a soccer season, four families decide to buy the coach a gift certificate to a sporting goods store. Each family contributes $35 towards the gift certificate. Write and solve a division equation to find how much the gift certificate is worth. g/35 = 4 g = $140 Jennifer and 3 friends went to dinner. If they each paid $11.25, how much was the total bill? d/3 = $11.25 d = $45