Unit 3 Math Review

Solve Using Distribution

100

4 x 62

4 x (60 + 2)

(4 x 60) + (4 x 2)

240 + 8

248

200

4 x 605

4 x (600 + 5)

(4 x 600) + (4 x 5)

2,400 + 20

2,420

300

5 x 324

5 x (300 + 20 + 4)

(5 x 300) + (5 x 20) + (5 x 4)

1,500 + 100 + 20 

1,620

400

6 x 1,120

6 x (1,000 + 100 + 20)

(6 x 1,000) + (6 x 100) + (6 x 20)

6,000 + 600 + 120

6,720

500

8 x 1,235

8 x (1,000 + 200 +30 + 5)

(8 x 1,000) + (8 x 200) + (8 x 30) + (8 x 5)

8,000 + 1,600 + 240 + 40

9,880

Solve Using Partial Product

100

2 x 68

2 x 60 = 120

2 x 8 = 16

120 + 16 = 136

200

5 x 84

5 x 80 = 400

5 x 4 = 20

400 + 20 = 420

300

5 x 194 

5 x 100 = 500

5 x 90 = 450 

5 x 4 = 20

500 + 450 + 20 = 970

400

6 x 1,105

6 x 1,000 = 6,000

6 x 100 = 600

6 x 5 = 30

6,000 + 600 + 30 = 6,630

500

7 x 2,525

7 x 2,000 = 14,000

7 x 500 = 3,500

7 x 20 = 140 

7 x 5 = 35 

14,000 + 3,500 + 140 + 35 = 17,675

Solve Using Standard Algorithm

100

2 x 35

70 

(show regrouping)

200

5 x 120 

600 

(show regrouping)

300

3 x 678

2,034 

(show regrouping)

400

5 x 1,130

5,650

(show regrouping)

500

9 x 1,005 

9,045

(show regrouping)

Estimate the Answer

100

Is 600 a reasonable answer for 5 x 10?

No

(explanations vary)

200

Is 900 a reasonable estimation for 9 x 98

Yes 

(explanations vary)

300

Is 1,000 a reasonable estimate for 1 x 100

No 

(explanations vary)

400

What is a reasonable estimate for 5 x 432?

2,000 / 2,100 

(answers vary, explanations needed)

500

What is a reasonable estimate for 7 x 2,345

14,000 - 16,000

(answers vary, explanation needed)

Word Problems

100

Amelia has a collection of 34 dolls. A toy store has 5 times as many dolls. How many dolls does the toy store have?

170 

How did you solve this problem? What key words helped you solve that? What did you circle/ box or underline?

200

Charlie drove 102 miles on Sunday. Nada drove 3 times as many miles on Saturday? How many miles did Nada drive?

306 miles

How did you solve this problem? What keywords helped you? What did you circle/ box or underline?

300

Edin rode the train 198 miles round trip 4 times last month. How many miles did Edin ride on the train?

792

How did you solve this problem? What keywords helped you? What did you circle/ box or underline?

400

Julian sets up a display placing 126 painted rocks in each of 3 rows. How many rocks does Julian display altogether?

378 

How did you solve this problem? What keywords helped you? What did you circle/ box or underline?

500

Alex sells tortillas in bags of 25 and 50. If he sells 4 bags of 50, how many tortillas does he sell? 

200

How did you solve this problem? What keywords helped you? What did you circle/ box or underline?