Question

using reasoning and estimation to calculate with decimals - item 55608
for each expression, round the terms to the nearest whole number.
then identify whether the estimated product will be greater than or less than the
actual product.
3.6 + 4.8 6.35 + 3.4 7.9 × 4.85 2.3 × 4.15
estimate is less than the actual answer. estimate is greater than the actual answer.
drag and drop items here drag and drop items here

Explanation:

Step1: Analyze \( 3.6 + 4.8 \)

Round \( 3.6 \) to \( 4 \) (nearest whole number) and \( 4.8 \) to \( 5 \). Estimated sum: \( 4 + 5 = 9 \). Actual sum: \( 3.6 + 4.8 = 8.4 \). Estimate (\( 9 \)) > Actual (\( 8.4 \)).

Step2: Analyze \( 6.35 + 3.4 \)

Round \( 6.35 \) to \( 6 \) and \( 3.4 \) to \( 3 \). Estimated sum: \( 6 + 3 = 9 \). Actual sum: \( 6.35 + 3.4 = 9.75 \). Estimate (\( 9 \)) < Actual (\( 9.75 \)).

Step3: Analyze \( 7.9 \times 4.85 \)

Round \( 7.9 \) to \( 8 \) and \( 4.85 \) to \( 5 \). Estimated product: \( 8 \times 5 = 40 \). Actual product: \( 7.9 \times 4.85 = 38.315 \). Estimate (\( 40 \)) > Actual (\( 38.315 \)).

Step4: Analyze \( 2.3 \times 4.15 \)

Round \( 2.3 \) to \( 2 \) and \( 4.15 \) to \( 4 \). Estimated product: \( 2 \times 4 = 8 \). Actual product: \( 2.3 \times 4.15 = 9.545 \). Estimate (\( 8 \)) < Actual (\( 9.545 \)).

Answer:

• Estimate is less than the actual answer: \( 6.35 + 3.4 \), \( 2.3 \times 4.15 \)
• Estimate is greater than the actual answer: \( 3.6 + 4.8 \), \( 7.9 \times 4.85 \)