1.
Musa's dig site is marked off into 9 squares, and each square has 8 fossil bones buried in it. The team has already lifted out 25 of the bones. How many bones are still in the ground?
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Answer:
Did you know? Diggers stretch string across a site to make a grid, so they can write down exactly which square every bone came from.
2.
Idris finds 63 fossil teeth. He sets aside 7 of them for the museum display case, then packs the rest equally into 8 boxes. How many teeth go in each box?
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Answer:
Did you know? A T. rex grew new teeth its whole life. The biggest ones were about as long as a banana.
3.
A museum has 428 fossils. It lends 175 of them to a museum in another city, then brings back 132 new fossils from a summer dig. How many fossils does the museum have now?
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Answer:
Did you know? Most of a museum's fossils are never on display — they sit in back rooms so scientists can study them.
4.
A dig starts at 8:15 a.m. The team digs for 55 minutes, takes a 20-minute water break, then digs for another 45 minutes. What time do they stop?
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Answer:
Did you know? A fossil isn't really bone anymore. Over thousands of years, water slowly swaps the bone out for minerals — turning it to stone.
5.
The team has to carry 58 rock samples back to camp. Each backpack holds exactly 9 samples. How many backpacks can be filled completely, and how many samples are left over?
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Answer:
Did you know? Diggers carry home the plain rock around a fossil too. Tiny teeth and seeds often hide inside it.
1.
A museum unpacks 24 crates of fossil casts, and each crate holds 15 casts. The casts are shared equally among 9 school classrooms. How many casts does each classroom get?
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Answer:
Did you know? A cast is a copy made from a mold of a real fossil. Most dinosaur skeletons you see standing in a museum are casts — the real bones are too heavy and too precious.
2.
Yusuf saves $8 every week for 14 weeks to buy fossil-hunting gear. A rock hammer costs $46 and a set of brushes costs $19. How much money does he have left?
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Answer:
Did you know? Most of the digging near a fossil is done with brushes and dental picks, not shovels — one wrong swing can snap a 100-million-year-old bone.
3.
A rectangular quarry floor measures 38 meters long and 24 meters wide. What is its area? If each dig team is given 48 square meters to work on, how many teams can work on the floor at the same time?
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Answer:
Did you know? Lots of dinosaurs are first found in quarries and road cuts, because digging there slices open rock layers that had been buried for ages.
4.
A skeleton being rebuilt in the museum has 36 bones in all. On Monday the team attaches 9 bones, and on Tuesday they attach 18 more. What fraction of the skeleton is attached, and what fraction is still missing? Write both fractions in simplest form.
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Answer:
Did you know? No complete T. rex has ever been found. The most complete one, nicknamed Sue, is about 90% there — the rest is filled in with copies.
5.
A dinosaur exhibit sells 1,275 tickets every day for 8 days. The museum planned for 12,000 visitors over that stretch. How many tickets were sold, and how many spots are still open?
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Answer:
Did you know? Argentinosaurus may have weighed as much as 10 elephants — one of the heaviest animals ever to walk on land.
3rd Grade
1. 47 bones still buried.
9 squares × 8 bones = 72. Then 72 − 25 already lifted = 47.
2. 7 teeth per box.
63 − 7 for the display = 56. Then 56 ÷ 8 boxes = 7.
3. 385 fossils.
428 − 175 lent out = 253. Then 253 + 132 new = 385.
4. 10:15 a.m.
55 + 20 + 45 = 120 minutes = 2 hours. Then 8:15 a.m. + 2 hr = 10:15 a.m.
5. 6 full backpacks, 4 samples left over.
58 ÷ 9 = 6 remainder 4. 6 backpacks full, 4 samples left (they'd need a 7th backpack).
4th Grade
1. 40 casts per classroom.
24 crates × 15 casts = 360. Then 360 ÷ 9 classrooms = 40.
2. $47 left.
$8 × 14 weeks = $112 saved. Then $112 − $46 − $19 = $47.
3. Area = 912 sq m; 19 teams.
38 × 24 = 912 square meters. Then 912 ÷ 48 = 19 teams.
4. Attached 27/36 = 3/4; missing 9/36 = 1/4.
9 + 18 = 27 bones attached. 27/36 simplifies to 3/4. Missing: 36 − 27 = 9, so 9/36 = 1/4.
5. 10,200 tickets sold; 1,800 spots open.
1,275 × 8 days = 10,200. Then 12,000 − 10,200 = 1,800 left.