Curriculum›4A›Chapter 4

Practice A: Multiplication

Chapter 4 · Consolidation 1

Mixed consolidation. Attempt problems independently before revealing the solutions.

Question 1 · calculation

Calculate 25 × 7 using a split or friendly number.

Show answer & reasoning
175

Split 25 into 20 + 5. Then multiply each part by 7 and add the partial products.

Question 2 · calculation

Calculate 82 × 5.

Show answer & reasoning
410

82 × 5 = (80 × 5) + (2 × 5) = 410. Each partial product uses its correct place value.

Question 3 · calculation

Calculate 172 × 3.

Show answer & reasoning
516

172 × 3 = (170 × 3) + (2 × 3) = 516. Each partial product uses its correct place value.

Question 4 · calculation

Calculate 44 × 90.

Show answer & reasoning
3,960

90 represents 9 tens. Multiply by 9, then scale by 10 to obtain 3,960.

Question 5 · area model

Find 63 × 67 using an area model or partial products.

Show answer & reasoning
4,221

Expand (60+3)(60+7) = 3600+420+180+21 = 4221.

Question 6 · area model

Find 374 × 63 using an area model or partial products.

Show answer & reasoning
23,562

Expand (370+4)(60+3) = 22200+1110+240+12 = 23562.

Question 7 · calculation

Calculate 21 × 9 using a split or friendly number.

Show answer & reasoning
189

Split 21 into 20 + 1. Then multiply each part by 9 and add the partial products.

Question 8 · calculation

Calculate 40 × 2.

Show answer & reasoning
80

40 × 2 = (40 × 2) + (0 × 2) = 80. Each partial product uses its correct place value.

Question 9 · calculation

Calculate 186 × 6.

Show answer & reasoning
1,116

186 × 6 = (180 × 6) + (6 × 6) = 1116. Each partial product uses its correct place value.

Question 10 · calculation

Calculate 320 × 60.

Show answer & reasoning
19,200

60 represents 6 tens. Multiply by 6, then scale by 10 to obtain 19,200.

Question 11 · area model

Find 35 × 58 using an area model or partial products.

Show answer & reasoning
2,030

Expand (30+5)(50+8) = 1500+240+250+40 = 2030.

Question 12 · area model

Find 77 × 63 using an area model or partial products.

Show answer & reasoning
4,851

Expand (70+7)(60+3) = 4200+210+420+21 = 4851.

Question 13 · calculation

Calculate 23 × 8 using a split or friendly number.

Show answer & reasoning
184

Split 23 into 20 + 3. Then multiply each part by 8 and add the partial products.

Question 14 · calculation

Calculate 97 × 4.

Show answer & reasoning
388

97 × 4 = (90 × 4) + (7 × 4) = 388. Each partial product uses its correct place value.

Question 15 · calculation

Calculate 40 × 3.

Show answer & reasoning
120

40 × 3 = (40 × 3) + (0 × 3) = 120. Each partial product uses its correct place value.

Question 16 · calculation

Calculate 116 × 30.

Show answer & reasoning
3,480

30 represents 3 tens. Multiply by 3, then scale by 10 to obtain 3,480.

Question 17 · area model

Find 55 × 20 using an area model or partial products.

Show answer & reasoning
1,100

Expand (50+5)(20+0) = 1000+0+100+0 = 1100.

Question 18 · area model

Find 254 × 15 using an area model or partial products.

Show answer & reasoning
3,810

Expand (250+4)(10+5) = 2500+1250+40+20 = 3810.