Defining Variables Word Problems

After paying $5.12 for a salad, Nori has $27.10. How much money, m, did he have before buying the salad?

• m + $5.12 = $27.10

• $27.10 + $5.12= m

• $27.10= m- $5.12

• m = $27.10 - $5.12

Sue bought 3 t-shirts for $8 each. She paid with a $50 bill. How could you find how much change,c, should she get back?

• 50 - (8x3) = c

• (8x3) + 50 = c

• cx3x8 = 50

• 8 + 3 + 50 = c

Jim has one dollar. He spends 16 cents on a pencil. Jim's dad gives him five dollars for mowing the grass. Write an equation with a letter for the unknown to find out how much money Jim has now.

• 1.00 - .16 = m

• m =1.00

• $1.00 - $.16 + $5.00 = m

• 5 +1 + 16 = m

Ronnie needs 101 cupcakes for a birthday party. He already has 21 chocolate cupcakes and 33 vanilla cupcakes. How could you find how many more cupcakes,c, should Ronnie buy?

• c=33 + 101 - 21

• 101- (33 +21) =c

• 101- (33-21) =c

• (33 - 21) + c =101

18 A family spent $93 at a carnival. • They spent $18 on tickets to the carnival and $36 on food. • They spent the rest of the money on games. Which equation can be used to find g, the amount of money in dollars the family spent on games?

• F 93 = g + 36 − 18

• G 93 = 18 + 36 − g

• H 93 = 36 − 18 − g

• J 93 = g + 36 + 18

Barry needs $1,449 for summer camp. Two local clubs will each match what he saves. Barry has 3 months before he leaves for summer camp. How much does Barry need to save on his own each month to have enough for summer camp?

Brenda has 13 white buttons. She has 4 fewer brown buttons than white buttons. Brenda has 5 more gray buttons than brown buttons. How many gray buttons does Brenda have?

• (13 - 4) - 5

• (13 + 4) + 5

• (13 - 4) + 5

• (13 + 4) - 5

Robert has 54 pencils. He has 1 box of pencils and 3 packages of pencils. The box has 24 pencils. Which equation can be used to find p, the number of pencils in each package?

• p = 54 + (3 x 24)

• 24 = 54 + (3 x p)

• 54 = 3 + (24 x p)

• 54 = 24 + (3 x p)

WRITE AN EQUATION Aliyah had $24 to spend on pencils. After buying them she had $10. How much did she spend,s, on pencils?

• $24+$10=s

• $10-$24=s

• $24/s = $10

• $10+s= $24

A variable represents what is ______________. 

• the answer

• the operation

• the difference

• unknown