G5 11/5 Unit 7 & 8 Review

Harvest Totals

100

A farmer harvested 14.26 pounds of apples in the morning and 11.57 pounds in the afternoon.

Question: How many pounds were harvested altogether?

25.83 pounds

200

A booth received 23.48 pounds of pumpkins and later received 17.65 pounds more.

Question: What is the total amount of pumpkins received?

41.13 pounds

300

A produce stand received 8.764 pounds of carrots and 9.587 pounds later in the day.

Question: What is the total amount of carrots received?

18.351 pounds

What's Left

100

A basket started with 52.80 pounds of apples. Workers sold 27.45 pounds.

Question: How many pounds remain?

25.35 pounds

200

A cider stand started with 38.25 gallons of cider. Customers purchased 19.68 gallons.

Question: How much cider remains?

18.57 gallons

300

A vendor started with 61.400 pounds of produce. The vendor sold 28.975 pounds.

Question: How much produce remains?

32.425 pounds

Harvest Predictions

100

Estimate:

57.42 − 21.88

Question: What is a reasonable estimate?

✅ 35

• Rounded to the nearest whole number:
  • 57.42 ≈ 57
  • 21.88 ≈ 22
  • 57 − 22 = 35

✅ 36

• Used compatible numbers:
  • 58 − 22 = 36

✅ 30

• Used front-end estimation:
  • 50 − 20 = 30

The exact answer is 35.54. Any estimate close to 35 is reasonable

200

184.37 − 92.61

Question: What is a reasonable estimate?

✅ 91

• Rounded to whole numbers:
  • 184 − 93 = 91

✅ 92

• Used compatible numbers:
  • 185 − 93 = 92

✅ 90

• Used front-end estimation:
  • 180 − 90 = 90

The exact answer is 91.76. Estimates between 90 and 92 are reasonable.

300

Estimate using compatible numbers:

398.12 − 248.95

Question: What is a reasonable estimate?

Use compatible numbers, or friendly numbers, to create a reasonable estimate. Be ready to explain how you chose them.

✅ 150

• 400 − 250 = 150
• This is the most common compatible-number estimate.

✅ 148

• 398 − 250 = 148
• Uses one friendly number and one unchanged number.

✅ 149

• 399 − 250 = 149
• Uses a nearby friendly number.

✅ 151

• 400 − 249 = 151
• Another reasonable compatible-number estimate.

The exact answer is 149.17.

The best compatible-number estimate is usually:

400 − 250 = 150

because both numbers are easy to subtract mentally.

Final Jeopardy

400

TIE BREAKER

A market stand received 12.345 pounds of strawberries and 9.876 pounds later in the day. Then it sold 7.221 pounds.

Question: How many pounds of strawberries remain?

15.000 pounds (or 15 pounds) 🍓🏆

500

The Harvest Market started the day with 248.650 pounds of apples.

Customers purchased 86.375 pounds.

Later, farmers delivered 24.825 pounds of apples.

Questions

1. How many pounds remained after the apples were sold?
2. What was the new total after the delivery?
3. Estimate the final amount.
4. Explain why your answer is reasonable.

After the sale: 162.275 pounds

New total: 187.100 pounds

Estimate: About 188 pounds

Reasonable because: The estimate (188) is very close to the exact answer (187.100).