Answer :
To determine which expression has an estimated product of 45, let's estimate each multiplication using simple rounding and calculations:
1. Estimate [tex]\(44.7 \times 2.1\)[/tex]:
- Round 44.7 to 45.
- Round 2.1 to 2.
- Calculate: [tex]\(45 \times 2 = 90\)[/tex].
2. Estimate [tex]\(7.5 \times 8.4\)[/tex]:
- Round 7.5 to 8.
- Round 8.4 to 8.
- Calculate: [tex]\(8 \times 8 = 64\)[/tex].
3. Estimate [tex]\(8.7 \times 5.28\)[/tex]:
- Round 8.7 to 9.
- Round 5.28 to 5.
- Calculate: [tex]\(9 \times 5 = 45\)[/tex].
4. Estimate [tex]\(38.1 \times 7.3\)[/tex]:
- Round 38.1 to 40.
- Round 7.3 to 7.
- Calculate: [tex]\(40 \times 7 = 280\)[/tex].
Among these estimates, the one closest to 45 is [tex]\(9 \times 5\)[/tex], which corresponds to the product of [tex]\(8.7 \times 5.28\)[/tex]. So, this expression has an estimated product of 45.
1. Estimate [tex]\(44.7 \times 2.1\)[/tex]:
- Round 44.7 to 45.
- Round 2.1 to 2.
- Calculate: [tex]\(45 \times 2 = 90\)[/tex].
2. Estimate [tex]\(7.5 \times 8.4\)[/tex]:
- Round 7.5 to 8.
- Round 8.4 to 8.
- Calculate: [tex]\(8 \times 8 = 64\)[/tex].
3. Estimate [tex]\(8.7 \times 5.28\)[/tex]:
- Round 8.7 to 9.
- Round 5.28 to 5.
- Calculate: [tex]\(9 \times 5 = 45\)[/tex].
4. Estimate [tex]\(38.1 \times 7.3\)[/tex]:
- Round 38.1 to 40.
- Round 7.3 to 7.
- Calculate: [tex]\(40 \times 7 = 280\)[/tex].
Among these estimates, the one closest to 45 is [tex]\(9 \times 5\)[/tex], which corresponds to the product of [tex]\(8.7 \times 5.28\)[/tex]. So, this expression has an estimated product of 45.
