Worksheet Grade 4 Math
Ottercomb Isle's Water Barge: Sharing, Filling, and Rounding
A grade 4 worksheet where students divide a fictional island barge's daily fresh-water output among villages and tanks, interpret remainders, and round totals.
Objectives
- Students will divide a four-digit gallon total by a one-digit divisor and state both the quotient and the remainder.
- Students will decide when a remainder forces one more container.
- Students will round four-digit gallon totals to the nearest hundred and to the nearest thousand.
Vocabulary
Key words: barge, village, remainder, round, supply
Teacher overview
Ottercomb Isle is a fictional island with no river and only a few shallow wells, so a barge tied up at the town pier carries a machine that pulls salt out of sea water and turns it into fresh water. The crew shares each day's output among the island's villages and pours the rest into portable tanks that boats carry to the smaller landings. The misconception this worksheet is built to correct is dropping a remainder when the remainder still represents real water: a student who divides 1,725 gallons into 8-gallon tanks and reports 215 tanks has left 5 gallons sitting on the barge with nowhere to go. Watch also for students who round 1,725 to the nearest thousand by looking at the tens digit rather than the hundreds digit.
Student Worksheet
The barge crew keeps a daily log. Use the numbers given in each item.
The barge made 2,184 gallons of fresh water on Monday. The island has 6 villages. Each village gets the same amount. How many gallons does each village get?
Round 2,184 gallons to the nearest hundred.
On Tuesday the barge made 1,725 gallons. Each tank holds 8 gallons. How many tanks can the crew fill all the way?
The barge made 1,725 gallons. The crew filled 215 tanks that hold 8 gallons each. How many gallons are left on the barge?
The crew will not leave any water on the barge. Each tank holds 8 gallons. How many tanks does the crew need for all 1,725 gallons?
Round 1,725 gallons to the nearest thousand.
The barge makes 2,184 gallons every day. How many gallons does it make in 4 days?
Round 8,736 gallons to the nearest thousand.
On Monday the barge made 2,184 gallons. The island used 900 gallons that day. How many gallons were left?
The crew reports "about 2,000 gallons" instead of 2,184 gallons. Explain why a rounded number helps the island. Write one or two sentences.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Answer Key
Answer: 364 gallons.
Divide 2,184 by 6. Six goes into 21 hundreds 3 times with 3 hundreds left, into 38 tens 6 times with 2 tens left, and into 24 ones 4 times with none left. The quotient is 364 gallons and there is no remainder. Check: 364 times 6 equals 2,184.Answer: 2,200 gallons.
To round to the nearest hundred, look at the tens digit of 2,184, which is 8. Because 8 is 5 or greater, the hundreds digit goes up from 1 to 2, giving 2,200 gallons.Answer: 215 tanks.
Divide 1,725 by 8. Eight goes into 17 hundreds 2 times with 1 hundred left, into 12 tens 1 time with 4 tens left, and into 45 ones 5 times with 5 ones left. The quotient is 215 with a remainder of 5. Check: 215 times 8 equals 1,720.Answer: 5 gallons.
The 215 full tanks hold 215 times 8, which is 1,720 gallons. Subtract that from the day's output: 1,725 minus 1,720 equals 5 gallons. This is the same 5 that appeared as the remainder in item 3.Answer: 216 tanks.
The 215 full tanks leave 5 gallons behind, and those 5 gallons still need somewhere to go. One more tank holds them, so the crew needs 215 plus 1, or 216 tanks. The last tank will be only part full.Answer: 2,000 gallons.
To round to the nearest thousand, look at the hundreds digit of 1,725, which is 7. Because 7 is 5 or greater, the thousands digit goes up from 1 to 2, giving 2,000 gallons.Answer: 8,736 gallons.
Multiply 2,184 by 4 in parts: 2,000 times 4 equals 8,000, 100 times 4 equals 400, 80 times 4 equals 320, and 4 times 4 equals 16. Adding 8,000 plus 400 plus 320 plus 16 gives 8,736 gallons.Answer: 9,000 gallons.
Look at the hundreds digit of 8,736, which is 7. Because 7 is 5 or greater, the thousands digit goes up from 8 to 9, giving 9,000 gallons.Answer: 1,284 gallons.
Subtract 900 from 2,184. Take away 200 to reach 1,984, then take away 700 to reach 1,284 gallons.Answer: A rounded number is quicker to read and remember.
Accept any explanation stating that "about 2,000 gallons" gives islanders a fast sense of how much water arrived and is easy to compare with other days, while the exact figure of 2,184 gallons stays in the crew's log for anyone who needs to check it.
Differentiation
Support (below grade level)
Provide a version of the worksheet with the long-division frames for items 1 and 3 already set up, showing the dividend and divisor in place and boxes waiting for the quotient and remainder. Give students base-ten blocks or a place-value chart for the rounding items and let them circle the deciding digit before they write. Reduce the assignment to items 1, 2, 3, 4, and 5.
Extension (above grade level)
Ask students to plan a full week for the fictional Ottercomb Isle barge. The barge makes 2,184 gallons on four days and 1,725 gallons on three days, and every gallon must go into 8-gallon tanks. Students find the week's total, the number of tanks needed each day, the number of tanks needed for the week, and the day with the largest leftover, then explain why the weekly tank count is not simply the weekly total divided by 8.
ELL supports
Pre-teach "barge," "village," and "left over" with a labeled drawing showing a flat boat at a pier, a row of small tanks on the deck, and one tank only partly shaded. Provide sentence frames for items 5 and 10: "The crew needs ___ tanks because ___ gallons are still left," and "A rounded number helps because ___." Allow students to explain item 10 to a partner before writing it.
Extensions
Students can compare the fictional Ottercomb barge with a real island community's water supply, listing the sources each one uses and how often supplies arrive. A class ready for more arithmetic can recalculate the whole worksheet with tanks that hold 12 gallons instead of 8 and describe what happens to both the tank count and the leftover amount.