五年级第二学期数学代数训练

顾卿璇

I. Choose the correct options.

1. Mrs. Smith buys 7 boxes of matches. They are on sale for $2each. The letter c stands for the total cost. Which equation canyou use to find c？

A. 7 – 2 = c B. 7 × 2 = c

2. Mrs. Tang opened a box of 20 pencils. She threw out 1 brokenpencil and kept the rest. The letter k stands for the number ofpencils she kept. Which equation can you use to find k？

A. 20 – 1 = k B. 20 + 1 = k

3. Lucia is decorating for a surprise party. She takes 30 balloonsand splits them into bunches with 6 balloons each. The letter bstands for the number of bunches. Which equation can you useto find b？

A. 30 – 6 = b B. 30 ÷ 6 = b

4. Abby is saving up for her friend Zanes birthday gift. Everyweek for 5 weeks in a row， Abby saves $5. The letter m standsfor the total amount of money Abby will save. Which equationcan you use to find m？

A. 5 × 5 = m B. 5 + 5 = m

5. Ellen has 15 marbles. Carlos has 12 marbles. They decide to puttheir marbles together for a game. The letter m stands for thetotal number of marbles. Which equation can you use to find m？

A. 15 – 12 = m B. 15 + 12 = m

II. Find the value of the variable.

1. Use the equation k = t – 5 to find the value of k when t = 7.

2. Use the equation a = n + 9 to find the value of a when n = 1.

3. Use the equation q = r – 3 to find the value of q when r = 8.

4. Use the equation j = b + 9 to find the value of j when b = 6.

5. Use the equation v = g – 3 to find the value of v when g = 4.