🦕 DinosaursGrade 3Reading: grades 7-9MultiplicationRoundingAdditionSubtractionDivision

The Cretaceous Outpost Sabotage

A priceless, perfectly preserved prehistoric specimen was stolen overnight from the secure vault at Titan Valley Outpost. The perpetrator bypassed security using trained prehistoric wildlife and specialized tactical gear, leaving behind scattered evidence across the excavating trenches.

Suspects

Possible suspects

Cross off a row as each clue rules it out. On screen, tap a row.

21 of 21 still in play

Name	Dino Companion	Field Gear	Dominant Hand	Crest Color	Scent Foil
Ray Arnold	Triceratops	Tranquilizer Rifle	Right Handed	Obsidian Crest	Citrus Mist
Billy Brennan	Ankylosaurus	Thermal Goggles	Right Handed	Crimson Crest	Pine Resin
Franklin Webb	Triceratops	Thermal Goggles	Left Handed	Crimson Crest	Pine Resin
Roland Tembo	Stegosaurus	Thermal Goggles	Right Handed	Amber Crest	Eucalyptus Spray
Dr Henry Wu	Pterodactyl	Tranquilizer Rifle	Left Handed	Obsidian Crest	Pine Resin
Sarah Harding	Pterodactyl	Sonic Whistle	Right Handed	Crimson Crest	Eucalyptus Spray
Nick Van Owen	Pterodactyl	Grappling Launcher	Left Handed	Crimson Crest	Eucalyptus Spray
Dr Charlotte Lockwood	Stegosaurus	Grappling Launcher	Right Handed	Obsidian Crest	Pine Resin
Dennis Nedry	Ankylosaurus	Sonic Whistle	Left Handed	Crimson Crest	Eucalyptus Spray
Darius Bowman	Stegosaurus	Sonic Whistle	Left Handed	Crimson Crest	Eucalyptus Spray
Vivian Krill	Ankylosaurus	Drone Scanner	Left Handed	Obsidian Crest	Citrus Mist
Dr Ian Malcolm	Pterodactyl	Sonic Whistle	Left Handed	Amber Crest	Eucalyptus Spray
Dr Alan Grant	Velociraptor	Drone Scanner	Left Handed	Crimson Crest	Eucalyptus Spray
Simon Masrani	Stegosaurus	Drone Scanner	Left Handed	Crimson Crest	Pine Resin
Ramsay Cole	Ankylosaurus	Tranquilizer Rifle	Right Handed	Crimson Crest	Eucalyptus Spray
Kayla Watts	Stegosaurus	Grappling Launcher	Left Handed	Obsidian Crest	Eucalyptus Spray
Dr Ellie Sattler	Triceratops	Grappling Launcher	Left Handed	Crimson Crest	Eucalyptus Spray
Peter Ludlow	Triceratops	Tranquilizer Rifle	Right Handed	Crimson Crest	Eucalyptus Spray
Maisie Lockwood	Triceratops	Thermal Goggles	Right Handed	Obsidian Crest	Pine Resin
Lowery Cruthers	Pterodactyl	Thermal Goggles	Left Handed	Crimson Crest	Citrus Mist
Zia Rodriguez	Pterodactyl	Tranquilizer Rifle	Right Handed	Obsidian Crest	Citrus Mist

Clue 1

Multiplication facts (1-12)

To decode the first encrypted clue, you calculate the total fossil samples by organizing equal storage trays into groups.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

108

5 × 1 =T

5 × 11 =D

6 × 3 =O

8 × 6 =P

2 × 8 =C

6 × 12 =A

8 × 1 =U

5 × 5 =R

12 × 9 =N

9 × 9 =S

10 × 7 =E

7 × 3 =H

0/12 letters found

Clue 2

Rounding

The digital expedition radar only displays proximity distance rounded to the nearest hundred meters, masking exact coordinates.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

600

500

4000

200

600

6000

4000

300

500

3000

4000

500

800

6000

9000

7000

Round 648 to the nearest hundredW

Round 33 to the nearest tenI

Round 5,997 to the nearest thousandL

Round 47 to the nearest tenR

Round 309 to the nearest hundredF

Round 7,290 to the nearest thousandK

Round 2,911 to the nearest thousandH

Round 8,541 to the nearest thousandM

Round 3,767 to the nearest thousandE

Round 73 to the nearest tenA

Round 804 to the nearest hundredO

Round 57 to the nearest tenD

Round 40 to the nearest tenN

Round 458 to the nearest hundredT

Round 202 to the nearest hundredS

0/15 letters found

Clue 3

Addition

Gathering field logs requires combining the inventory numbers from two separate dig trenches.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

378

338

261

868

309

272

463

455

338

520

463

318

868

272

427

309

921

261

812

378

837

455

960

378

655

202

309

868

202

269

520

463

868

455

960

151 + 227 =E

111 + 150 =C

184 + 271 =T

115 + 203 =R

174 + 253 =B

194 + 115 =L

252 + 211 =P

483 + 329 =K

94 + 108 =I

223 + 115 =U

456 + 381 =D

130 + 139 =N

185 + 87 =Y

432 + 436 =A

607 + 314 =O

618 + 342 =H

232 + 288 =S

368 + 287 =V

0/18 letters found

Clue 4

Subtraction

You determine how many tranquilizer darts were spent by subtracting the remaining inventory from the expedition crate.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

682

123

587

565

827

570

367

123

545

168

827

682

571

827

168

292

738

587

292

554

570

565

123

827

570

682

292

570

565

123

292

138

570

545

554

1005 - 323 =T

312 - 174 =M

993 - 166 =E

932 - 361 =H

798 - 228 =S

713 - 126 =A

421 - 54 =P

786 - 221 =C

1115 - 377 =L

731 - 186 =O

412 - 120 =I

185 - 62 =R

704 - 150 =N

231 - 63 =V

0/14 letters found

Clue 5

Division facts (1-12) — the last clue

Distributing the field rations equally among the research teams reveals the final encoded grid coordinate.

First solve each problem. Then find each answer in the list below and cross that sentence out. One sentence will be left — that's exactly what the villain did!

Step 1 — solve these

6 ÷ 6 = ?

120 ÷ 12 = ?

18 ÷ 9 = ?

64 ÷ 8 = ?

110 ÷ 10 = ?

20 ÷ 5 = ?

108 ÷ 12 = ?

54 ÷ 9 = ?

21 ÷ 3 = ?

20 ÷ 4 = ?

36 ÷ 3 = ?

Step 2 — cross out the sentence with each answer

1.The villain summoned a flying pterodactyl, then fired a heavy grappling launcher.

2.The villain guided an armored stegosaurus, then blew a high frequency sonic whistle.

3.The villain deployed a heavy ankylosaurus, then blew a high frequency sonic whistle.

4.The villain guided an armored stegosaurus, then fired a heavy grappling launcher.

5.The villain summoned a flying pterodactyl, then switched on custom thermal goggles.

6.The villain signaled a swift velociraptor, then blew a high frequency sonic whistle.

7.The villain signaled a swift velociraptor, then switched on custom thermal goggles.

8.The villain directed a charging triceratops, then launched an overhead drone scanner.

9.The villain summoned a flying pterodactyl, then launched an overhead drone scanner.

10.The villain directed a charging triceratops, then fired a heavy grappling launcher.

11.The villain guided an armored stegosaurus, then switched on custom thermal goggles.

12.The villain directed a charging triceratops, then aimed a quiet tranquilizer rifle.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Cretaceous Outpost Sabotage

Culprit: Dennis Nedry (Ankylosaurus · Sonic Whistle · Left Handed · Crimson Crest · Eucalyptus Spray)

Clue 1 (Multiplication facts (1-12)): "THE SUSPECT DOES NOT USE A DRONE SCANNER"
5 × 1 = 5 (T) · 5 × 11 = 55 (D) · 6 × 3 = 18 (O) · 8 × 6 = 48 (P) · 2 × 8 = 16 (C) · 6 × 12 = 72 (A) · 8 × 1 = 8 (U) · 5 × 5 = 25 (R) · 12 × 9 = 108 (N) · 9 × 9 = 81 (S) · 10 × 7 = 70 (E) · 7 × 3 = 21 (H)
Clue 2 (Rounding): "WITNESS SAW A LEFT HANDED TOOL MARK"
Round 648 to the nearest hundred = 600 (W) · Round 33 to the nearest ten = 30 (I) · Round 5,997 to the nearest thousand = 6000 (L) · Round 47 to the nearest ten = 50 (R) · Round 309 to the nearest hundred = 300 (F) · Round 7,290 to the nearest thousand = 7000 (K) · Round 2,911 to the nearest thousand = 3000 (H) · Round 8,541 to the nearest thousand = 9000 (M) · Round 3,767 to the nearest thousand = 4000 (E) · Round 73 to the nearest ten = 70 (A) · Round 804 to the nearest hundred = 800 (O) · Round 57 to the nearest ten = 60 (D) · Round 40 to the nearest ten = 40 (N) · Round 458 to the nearest hundred = 500 (T) · Round 202 to the nearest hundred = 200 (S)
Clue 3 (Addition): "EUCALYPTUS SPRAY BLOCKED THE VILLAINS PATH"
151 + 227 = 378 (E) · 111 + 150 = 261 (C) · 184 + 271 = 455 (T) · 115 + 203 = 318 (R) · 174 + 253 = 427 (B) · 194 + 115 = 309 (L) · 252 + 211 = 463 (P) · 483 + 329 = 812 (K) · 94 + 108 = 202 (I) · 223 + 115 = 338 (U) · 456 + 381 = 837 (D) · 130 + 139 = 269 (N) · 185 + 87 = 272 (Y) · 432 + 436 = 868 (A) · 607 + 314 = 921 (O) · 618 + 342 = 960 (H) · 232 + 288 = 520 (S) · 368 + 287 = 655 (V)
Clue 4 (Subtraction): "TRACES PROVE THE VILLAINS CREST IS CRIMSON"
1005 - 323 = 682 (T) · 312 - 174 = 138 (M) · 993 - 166 = 827 (E) · 932 - 361 = 571 (H) · 798 - 228 = 570 (S) · 713 - 126 = 587 (A) · 421 - 54 = 367 (P) · 786 - 221 = 565 (C) · 1115 - 377 = 738 (L) · 731 - 186 = 545 (O) · 412 - 120 = 292 (I) · 185 - 62 = 123 (R) · 704 - 150 = 554 (N) · 231 - 63 = 168 (V)
Clue 5 (Division facts (1-12)): surviving statement (box 3) → Dennis Nedry
6 ÷ 6 = 1 · 120 ÷ 12 = 10 · 18 ÷ 9 = 2 · 64 ÷ 8 = 8 · 110 ÷ 10 = 11 · 20 ÷ 5 = 4 · 108 ÷ 12 = 9 · 54 ÷ 9 = 6 · 21 ÷ 3 = 7 · 20 ÷ 4 = 5 · 36 ÷ 3 = 12

About this mystery

Grade level: Grade 3 math
Math topics: Multiplication, Rounding, Addition, Subtraction, Division
Reading level: grades 7-9
Theme: The Cretaceous Outpost Sabotage — set in Titan Valley Fossil Preserve
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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