4-8

Find the product of 231 and 7. Estimate first.

Step 1 Estimate.

200 × 7 = 1,400

4-8

Find the product of 231 and 7. Estimate first.

231 × 7

Step 2 Rewrite the problem in vertical format.

4-8

Find the product of 231 and 7. Estimate first.

231 × 7

Step 3 Multiply 7 times the digit in the ones column.

7

7 × 1 = 7

4-8

Find the product of 231 and 7. Estimate first.

231 × 7

Step 4 Multiply 7 times the digit in the tens column.

7 1

2

7 × 3 = 21

4-8

Find the product of 231 and 7. Estimate first.

231 × 7

Step 5 Multiply 7 times the digit in the hundreds column.

7 1

2Add two for 16.

1,6

7 × 2 = 14

4-8

Find the product of 231 and 7. Estimate first.

Step 6 The product is 1,617. Compare to your estimate for reasonableness.