Topic 5 Reteach

Topic 5 Reteach

Arrays & Multiplying 2x2-digit Multiples of 10

Mental Math

Using Rounding to Estimate

Using Compatible Numbers to Estimate

Multi-Step Problems

Multiple Choice

The array shows 24 rows of 30 squares. Which is a way to find the TOTAL number of squares.

• (30 x 20) + (30 x 4)

• 10 + 10 + 4 + 10 + 10 + 10

• (20 x 10) + (4 x 10)

• 300 + 240

Multiple Choice

There are 13 girls in Janelle's soccer team. Uniforms cost $32 each. Which equation uses estimation correctly to show ABOUT HOW MUCH money the team spent?

• 5 x $35 = $175

• 10 x $30 = $300

• 20 x $30 = $600

• 20 x $32 = $640

Multiple Choice

Mark's football team has scored about 24 points each game. They played 12 games this season. What is the best estimate for the total number of points they scored in the season? Use compatible numbers.

• 360

• 250

• 150

• 20

Multiple Choice

In a science contest, 30 students will present their science projects. Each student gets to talk for 20 minutes. How much time is needed to present all of the science projects?

• 1,800

• 610

• 600

• 50