1.
A ranger counts 7 flocks of snow geese with 128 birds in each flock. Later, 215 of those birds land on the lake. How many are still flying?
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Answer:
Did you know? Snow geese fly in a V. The bird at the point does the hardest work, so they take turns swapping places.
2.
154 tagged sandpipers must be moved to the coast. Each carrying crate holds 9 birds. How many crates are needed so that no bird is left behind?
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Answer:
Did you know? Some sandpipers fly from Alaska to New Zealand without landing once — over a week in the air.
3.
A ranger counts 168 monarch butterflies in the morning and 264 in the afternoon. She writes them all onto 8 record pages, the same number on each page. How many go on each page?
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Answer:
Did you know? No single monarch makes the whole round trip. It takes several generations, and the great-grandchildren still find the same forest.
4.
One tag box is 2/3 full. Another tag box is 5/8 full. Which box holds more tags?
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Answer:
Did you know? A bird tag can weigh less than a paperclip. Anything heavier would change how the bird flies.
5.
A rectangular nesting plot has an area of 132 square metres. One side is 12 m long. How long is the other side, and what is the perimeter of the plot?
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Answer:
Did you know? Arctic terns see two summers every year. They chase daylight from the Arctic to Antarctica and back.
1.
A tagging team fits 47 birds with trackers every day for 26 days. How many birds get a tracker altogether?
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Answer:
Did you know? A tracker the size of a pea can record a bird's whole route and send it up to a satellite.
2.
A tagged whale swam 3,461 km in 7 days, the same distance each day. How far did it swim per day, and how many km are left over?
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Answer:
Did you know? Grey whales make one of the longest migrations of any mammal — up to 20,000 km in a year.
3.
A boat starts with 5/6 of a tank of fuel. Following a herd uses 2/5 of a tank. What fraction of a tank is left?
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Answer:
Did you know? Wildebeest cross the same rivers every year. Over a million of them move together in one great loop.
4.
Bilal weighs one tracker at 3.6 g and a second at 1.85 g. What is their total weight, and how much heavier is the first than the second?
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Answer:
Did you know? Scientists keep a tracker under 3% of a bird's body weight — about the same rule as a backpack for you.
5.
A satellite logged 2,184 pings in 8 hours. At that same rate, how many pings does it log in 5 hours? If those pings are stored in files of 9, how many full files is that, and how many pings are left over?
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Answer:
Did you know? Migration maps are built from millions of pings like these, stitched together into one line across the world.
3rd Grade
1. 681 birds still flying.
128 × 7 = 896, then 896 − 215 = 681. Multiply first, subtract second — 128 − 215 is the give-away that the order slipped.
2. 18 crates.
154 ÷ 9 = 17 remainder 1. That 1 leftover bird still needs a crate, so round up to 18. “17” is the answer that ignores the question.
3. 54 butterflies per page.
168 + 264 = 432, then 432 ÷ 8 = 54. Add both halves of the day before splitting. Dividing 168 by 8 alone forgets the afternoon.
4. The 2/3 box.
Twenty-fourths: 2/3 = 16/24 and 5/8 = 15/24, so 2/3 is more. They are close on purpose — this one cannot be eyeballed.
5. Other side 11 m; perimeter 46 m.
132 ÷ 12 = 11 m (the missing side). Perimeter = 2 × (12 + 11) = 46 m. Given area, asked perimeter: divide for the side, don't halve.
4th Grade
1. 1,222 birds.
47 × 26 = (47 × 20) + (47 × 6) = 940 + 282 = 1,222. Two-digit by two-digit: the second partial row shifts one column left.
2. 494 km per day, 3 km left over.
3,461 ÷ 7 = 494 remainder 3. Check: 494 × 7 + 3 = 3,461. ✓ The question asks for both numbers.
3. 13/30 of a tank left.
Thirtieths: 5/6 = 25/30 and 2/5 = 12/30. 25/30 − 12/30 = 13/30. Unlike denominators — straight across gives 3/1, which is more than a full tank and fails its own sense check.
4. Total 5.45 g; the first is heavier by 1.75 g.
Write 3.6 as 3.60 and line the points up. 3.60 + 1.85 = 5.45; 3.60 − 1.85 = 1.75. The padding has to be written, not just thought.
5. 1,365 pings — 151 full files, 6 left over.
Rate first: 2,184 ÷ 8 = 273 per hour. Then 273 × 5 = 1,365. Then 1,365 ÷ 9 = 151 r 6. Check: 151 × 9 + 6 = 1,365. ✓