Practice with the help of **Spectrum Math Grade 5 Answer Key Chapter 5 Pretest **regularly and improve your accuracy in solving questions.

## Spectrum Math Grade 5 Chapter 5 Pretest Answers Key

**Check What You Know**

**Write each fraction in simplest form.**

Question 1.

a.

Answer: \(\frac{7}{8}\)

To add fractions with like denominators, add the numerators and use the common denominator.

\(\frac{1}{8}\) + \(\frac{6}{8}\) = \(\frac{1+6}{8}\) = \(\frac{7}{8}\)

b.

Answer: \(\frac{6}{7}\)

To add fractions with like denominators, add the numerators and use the common denominator.

\(\frac{3}{7}\) + \(\frac{3}{7}\) = \(\frac{3+3}{7}\) = \(\frac{6}{7}\)

c.

Answer: \(\frac{3}{6}\)

To add fractions with like denominators, add the numerators and use the common denominator.

\(\frac{2}{6}\) + \(\frac{1}{6}\) = \(\frac{2+1}{6}\) = \(\frac{3}{6}\)

d.

Answer: \(\frac{7}{9}\)

To add fractions with like denominators, add the numerators and use the common denominator.

\(\frac{4}{9}\) + \(\frac{3}{9}\) = \(\frac{4+3}{9}\) = \(\frac{7}{9}\)

Question 2.

a.

Answer: 1 \(\frac{1}{20}\)

To add fractions with like denominators, add the numerators and use the common denominator.

\(\frac{4}{5}\) + \(\frac{2}{8}\)

LCD is 40.

\(\frac{32}{40}\) + \(\frac{10}{40}\)

= \(\frac{32+10}{40}\) = \(\frac{42}{10}\) = 1 \(\frac{1}{20}\)

b.

Answer: 1

\(\frac{3}{6}\) + \(\frac{2}{4}\)

LCD is 12.

\(\frac{6}{12}\) + \(\frac{6}{12}\)

= \(\frac{6+6}{12}\) = \(\frac{12}{12}\) = 1

c.

Answer: 11 \(\frac{8}{9}\)

4\(\frac{2}{3}\) + 7\(\frac{2}{9}\)

4 + \(\frac{2}{3}\) + 7 + \(\frac{2}{9}\)

4 + 7 = 11

\(\frac{2}{3}\) + \(\frac{2}{9}\)

LCD is 9.

\(\frac{6}{9}\) + \(\frac{2}{9}\) = \(\frac{8}{9}\)

11 + \(\frac{8}{9}\) = 11\(\frac{8}{9}\)

d.

Answer: 7 \(\frac{37}{40}\)

1\(\frac{4}{5}\) + 6\(\frac{1}{8}\)

1 + \(\frac{4}{5}\) + 6 + \(\frac{1}{8}\)

1 + 6 = 7

\(\frac{4}{5}\) + \(\frac{1}{8}\)

LCD is 40.

\(\frac{32}{40}\) + \(\frac{5}{40}\) = \(\frac{37}{40}\)

7 + \(\frac{37}{40}\) = 7\(\frac{37}{40}\)

Question 3.

a.

Answer:

To subtract fractions with like denominators, subtract the numerators and use the common denominator.

\(\frac{7}{8}\) – \(\frac{1}{8}\) = \(\frac{7-1}{8}\) = \(\frac{6}{8}\) = \(\frac{3}{4}\)

b.

Answer:

To subtract fractions with like denominators, subtract the numerators and use the common denominator.

\(\frac{5}{9}\) – \(\frac{4}{9}\) = \(\frac{5-4}{9}\) = \(\frac{1}{9}\)

c.

Answer:

To subtract fractions with like denominators, subtract the numerators and use the common denominator.

\(\frac{8}{10}\) – \(\frac{3}{10}\) = \(\frac{8-3}{10}\) = \(\frac{5}{10}\)

d.

Answer:

To subtract fractions with like denominators, subtract the numerators and use the common denominator.

\(\frac{7}{12}\) – \(\frac{1}{12}\) = \(\frac{7-1}{12}\) = \(\frac{6}{12}\)

Question 4.

a.

Answer: \(\frac{1}{8}\)

\(\frac{7}{8}\) – \(\frac{3}{4}\)

LCD is 8.

\(\frac{7}{8}\) – \(\frac{6}{8}\)

\(\frac{7-6}{8}\) = \(\frac{1}{8}\)

b.

Answer: \(\frac{2}{35}\)

\(\frac{6}{7}\) – \(\frac{4}{5}\)

LCD is 35.

\(\frac{30}{35}\) – \(\frac{28}{35}\)

\(\frac{30-28}{8}\) = \(\frac{2}{35}\)

c.

Answer: \(\frac{22}{63}\)

\(\frac{4}{7}\) – \(\frac{2}{9}\)

LCD is 63.

\(\frac{36}{63}\) – \(\frac{14}{63}\)

\(\frac{36-14}{63}\) = \(\frac{22}{63}\)

d.

Answer: 4 \(\frac{1}{12}\)

6 \(\frac{1}{4}\) – 2\(\frac{1}{6}\)

6 + \(\frac{1}{4}\) – 2 – \(\frac{1}{6}\)

6 – 2 = 4

\(\frac{1}{4}\) – \(\frac{1}{6}\)

LCD is 12.

\(\frac{3}{12}\) – \(\frac{2}{12}\) = \(\frac{1}{12}\)

4 + \(\frac{1}{12}\) = 4\(\frac{1}{12}\)

**Solve each problem. Show your work.**

Question 5.

Julianne needs 7 yards of string for her kite. She has \(\frac{5}{8}\) yards. How many more yards does Julianne need for her kite?

Julianne needs _____________ more yards of string.

Answer:

Given,

Julianne needs 7 yards of string for her kite.

She has \(\frac{5}{8}\) yards.

7 – \(\frac{5}{8}\) = 6\(\frac{3}{8}\) yards

Julianne needs 6\(\frac{3}{8}\) more yards of string.

Question 6.

Mrs. Thompson’s cookie recipe includes \(\frac{1}{3}\) cup sugar and 4 cups flour. How many cups of sugar and flour does Mrs. Thompson need for her cookies?

Mrs. Thompson needs ______________ cups of ingredients.

Answer:

Given,

Mrs. Thompson’s cookie recipe includes \(\frac{1}{3}\) cup sugar and 4 cups flour.

\(\frac{1}{3}\) + 4 = 4\(\frac{1}{3}\)

Mrs. Thompson needs 4\(\frac{1}{3}\) cups of ingredients.

Question 7.

Marlon watched a movie 1\(\frac{8}{9}\) hours long. Jessie watched a movie 2\(\frac{2}{7}\) hours long. How much longer was Jessie’s movie than Marlon’s?

Jessie’s movie was _______________ hours longer.

Answer:

Given,

Marlon watched a movie 1\(\frac{8}{9}\) hours long. Jessie watched a movie 2\(\frac{2}{7}\) hours long.

2\(\frac{2}{7}\) – 1\(\frac{8}{9}\) = \(\frac{25}{63}\)

Jessie’s movie was \(\frac{25}{63}\) hours longer.

Question 8.

Carrie is running in a track meet. In one race she must run \(\frac{1}{4}\) mile, and in a second race she must run 1\(\frac{2}{5}\) miles. How many miles must Carrie run in all?

Carrie must run _____________ miles.

Answer:

Given,

Carrie is running in a track meet. In one race she must run \(\frac{1}{4}\) mile, and in a second race she must run 1\(\frac{2}{5}\) miles.

\(\frac{1}{4}\) + 1\(\frac{2}{5}\) = 1\(\frac{13}{20}\)

Carrie must run 1\(\frac{13}{20}\) miles.

Question 9.

David practiced soccer twice last week, On Monday, he practiced 2\(\frac{1}{3}\) hours. On Wednesday, he practiced 1\(\frac{7}{9}\) hours. How much longer did David practice on Monday?

David practiced _____________ hours longer on Monday.

Answer:

Given,

David practiced soccer twice last week, On Monday, he practiced 2\(\frac{1}{3}\) hours. On Wednesday, he practiced 1\(\frac{7}{9}\) hours.

2\(\frac{1}{3}\) – 1\(\frac{7}{9}\) = \(\frac{5}{9}\)

David practiced \(\frac{5}{9}\) hours longer on Monday.