1.
68 sailors must leave a ship. Each lifeboat holds 9. How many lifeboats are completely full, and how many lifeboats are launched altogether?
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Answer:
Did you know? A ship's speed is measured in knots, from the knots tied along a rope that sailors let run out behind them.
2.
A rope-maker produces 236 metres of rope a day for 3 days. Then 159 metres is cut away as damaged. How much good rope is left?
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Answer:
Did you know? A big sailing warship needed more than 30 km of rope in its rigging.
3.
6 ships each carry 14 crates. The crates are unloaded evenly across 7 ports. How many crates does each port receive?
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Answer:
Did you know? Tea clippers raced each other from China to London, and the first ship home got the best price for its cargo.
4.
One water barrel is 3/5 full. Another is 7/10 full. Which barrel holds more?
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Answer:
Did you know? Fresh water, not food, usually decided how long a voyage could last.
5.
A rectangular deck covers 72 square metres. One side is 8 m. Find the other side and the perimeter.
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Answer:
Did you know? Sailors marked time with a sandglass and a bell, ringing it every half hour through a four-hour watch.
1.
A voyage is 7/10 complete. The next leg adds another 1/4 of the whole voyage. What fraction is complete now?
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Answer:
Did you know? A lateen sail, triangular instead of square, lets a ship sail much closer to the wind — Arab dhows used them for centuries.
2.
3,428 litres of water are shared equally between 6 barrels. How much goes in each barrel, and how much is left over?
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Answer:
Did you know? Working out longitude at sea needed a clock accurate at sea — the problem took decades and a national prize to solve.
3.
A hold has 12.6 tonnes of cargo. At the first port 4.85 tonnes comes off. How much remains?
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Answer:
Did you know? Ships carry ballast — heavy weight low down — because an empty ship rides high and tips over more easily.
4.
A fleet of 62 ships each carries 45 barrels. How many barrels in the fleet?
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Answer:
Did you know? The Cutty Sark could cover more than 550 km in a single day with a good wind behind her.
5.
A ship sails at 8.5 nautical miles per hour for 14 hours, then a current pushes her back 23.5 nautical miles. How far has she actually made good?
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Answer:
Did you know? A nautical mile is one minute of latitude, which is why it is slightly longer than a mile on land.
3rd Grade
1. 7 full boats; 8 launched.
68 ÷ 9 = 7 remainder 5. You cannot leave 5 sailors aboard, so 8 boats go.
2. 549 metres.
236 × 3 = 708 m, then 708 − 159 = 549 m.
3. 12 crates each.
6 × 14 = 84 crates, then 84 ÷ 7 = 12.
4. The 7/10 barrel.
Tenths: 3/5 = 6/10. And 7/10 is more than 6/10.
5. Other side 9 m; perimeter 34 m.
72 ÷ 8 = 9 m. Perimeter = 8 + 9 + 8 + 9 = 34 m.
4th Grade
1. 19/20 of the voyage.
20ths: 7/10 = 14/20 and 1/4 = 5/20. 14/20 + 5/20 = 19/20 — not quite there yet.
2. 571 litres each, 2 left over.
3,428 ÷ 6 = 571 remainder 2. Check: 571 × 6 = 3,426, plus 2 = 3,428. ✓
3. 7.75 tonnes.
Pad it out: 12.60 − 4.85 = 7.75. The borrow across the decimal point is where this goes wrong.
4. 2,790 barrels.
62 × 45 = (62 × 40) + (62 × 5) = 2,480 + 310 = 2,790.
5. 95.5 nautical miles.
8.5 × 14 = 119, then 119 − 23.5 = 95.5.