🦕 DinosaursGrade 4Reading: grades 3-4Place valueRoundingAdditionSubtractionDivision

The Great Dino Lab Mix-Up

Oh no! Someone broke into the Dino Valley Lab and swapped the dinosaur DNA vials. Now we have a glowing T-Rex and a flying Triceratops! The Chief Paleontologist needs your help to catch the Rogue Ranger who did this before they escape the island.

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 Friend	Lab Gadget	Compass Hand	Field Hat	Dino Snack
Jack Horner	Riding a Raptor	Laser Scanner	Left Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Tracker Toby	Stomping a Stegosaurus	Laser Scanner	Right Handed Writer	Green Safari Hat	Tricked by Sweet Fruit
Alan Grant	Stomping a Stegosaurus	Sonic Dino Whistle	Right Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Charles Marsh	Stomping a Stegosaurus	Thermal Dino Tracker	Right Handed Writer	Tan Explorer Cap	Tricked by Sweet Fruit
Barnum Brown	Leading a Triceratops	DNA Mutator Ray	Right Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Ian Malcolm	Leading a Triceratops	Night Vision Goggles	Right Handed Writer	Tan Explorer Cap	Scared of Shiny Lights
Explorer Emily	Guiding a T-Rex	Thermal Dino Tracker	Right Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Macy Stone	Leading a Triceratops	Sonic Dino Whistle	Left Handed Writer	Brown Pith Helmet	Scared of Shiny Lights
Robert Bakker	Riding a Raptor	Night Vision Goggles	Right Handed Writer	Tan Explorer Cap	Tricked by Sweet Fruit
Sue Hendrickson	Leading a Triceratops	DNA Mutator Ray	Right Handed Writer	Brown Pith Helmet	Afraid of Loud Roars
Claire Dearing	Leading a Triceratops	Night Vision Goggles	Right Handed Writer	Tan Explorer Cap	Afraid of Loud Roars
Mary Anning	Leading a Triceratops	Laser Scanner	Right Handed Writer	Brown Pith Helmet	Scared of Shiny Lights
Gideon Mantell	Guiding a T-Rex	DNA Mutator Ray	Right Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Dino Dan	Flying a Pterodactyl	Laser Scanner	Left Handed Writer	Tan Explorer Cap	Scared of Shiny Lights
Ranger Owen	Flying a Pterodactyl	Laser Scanner	Right Handed Writer	Green Safari Hat	Tricked by Sweet Fruit
Bones Bailey	Leading a Triceratops	Night Vision Goggles	Right Handed Writer	Brown Pith Helmet	Tricked by Sweet Fruit
Roy Andrews	Stomping a Stegosaurus	DNA Mutator Ray	Left Handed Writer	Green Safari Hat	Afraid of Loud Roars
Ranger Rick	Riding a Raptor	Sonic Dino Whistle	Left Handed Writer	Tan Explorer Cap	Scared of Shiny Lights
Raptor Rex	Stomping a Stegosaurus	Thermal Dino Tracker	Left Handed Writer	Green Safari Hat	Tricked by Sweet Fruit
Dr Wu	Stomping a Stegosaurus	DNA Mutator Ray	Right Handed Writer	Green Safari Hat	Tricked by Sweet Fruit
Digging Daisy	Leading a Triceratops	DNA Mutator Ray	Left Handed Writer	Green Safari Hat	Afraid of Loud Roars

Clue 1

Place value

We checked the security code lock on the dino cage. The screen shows a mystery number. Find the value of the digit in the tens place to unlock the first clue!

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

100

1000

3000

400

100

800

1000

100

1000

8000

500

300

400

100

8000

9000

6000

1000

8000

What is the value of the 1 in 8,147?T

What is the value of the 5 in 158?O

What is the value of the 8 in 38,043?R

What is the value of the 6 in 6,270?K

What is the value of the 9 in 9,028?C

What is the value of the 3 in 538?A

What is the value of the 3 in 9,377?I

What is the value of the 7 in 279?L

What is the value of the 2 in 327?H

What is the value of the 3 in 3,022?Y

What is the value of the 5 in 560?M

What is the value of the 8 in 1,801?V

What is the value of the 1 in 1,087?E

What is the value of the 8 in 3,989?D

What is the value of the 4 in 471?N

0/15 letters found

Clue 2

Rounding

The lab radar tracks dinosaur footsteps. It only prints out numbers rounded to the nearest ten. Round this footprint count to see where the suspect went next!

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

290

2900

700

7000

1700

700

290

1100

9000

290

700

1300

4300

200

1100

9000

290

2900

290

2900

700

9000

170

2900

290

2900

110

4300

5000

Round 286 to the nearest tenT

Round 4,292 to the nearest hundredN

Round 8,543 to the nearest thousandI

Round 169 to the nearest tenG

Round 53 to the nearest tenL

Round 658 to the nearest hundredE

Round 22 to the nearest tenR

Round 2,911 to the nearest hundredH

Round 66 to the nearest tenS

Round 6,583 to the nearest thousandU

Round 1,739 to the nearest hundredP

Round 223 to the nearest hundredY

Round 4,748 to the nearest thousandD

Round 26 to the nearest tenC

Round 110 to the nearest tenA

Round 1,337 to the nearest hundredO

Round 1,088 to the nearest hundredW

0/17 letters found

Clue 3

Addition

We found dropped fossil pieces along the muddy trail. Add up the total number of fossils collected to find the suspect's path!

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

4740

8803

4965

9126

5674

5156

7077

4790

7077

5674

4790

9126

4978

4740

3654

3356

4473

3654

5985

4978

3654

8662

4965

4978

5674

4965

4740

4473

5985

5626

5156

4740

2655 + 2085 =T

6146 + 2657 =H

1910 + 1446 =P

3279 + 1699 =S

2557 + 4520 =L

1536 + 2118 =O

4022 + 4640 =M

3505 + 2480 =R

3619 + 5507 =Y

2933 + 1857 =A

2348 + 2617 =E

2211 + 3415 =U

2088 + 2385 =F

3500 + 2174 =W

2608 + 2548 =I

0/15 letters found

Clue 4

Subtraction

The baby triceratops ate some of our berry supplies. Subtract the eaten berries from our total inventory to see what clue was left behind!

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

8464

4299

7571

3387

3494

7571

8469

6710

4147

8464

4299

7615

7571

4362

6017

2383

6314

4097

7571

6017

8469

6949

2383

6314

6876

3494

4097

7615

8464

4299

7571

5983

6553

7571

8464

10164 - 1700 =T

4259 - 112 =Y

8093 - 3794 =H

8593 - 4496 =P

7621 - 4234 =S

10600 - 4047 =M

6890 - 873 =D

8200 - 629 =E

5913 - 1551 =F

6626 - 3132 =N

7425 - 549 =W

12717 - 4248 =A

9879 - 3169 =K

9037 - 1422 =I

4883 - 2500 =R

10540 - 3591 =B

10453 - 4139 =O

7001 - 1018 =L

0/18 letters found

Clue 5

Division facts (1-12) — the last clue

We have a bag of raptor treats to share equally among our patrol teams. Divide the treats evenly to find the final clue!

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

22 ÷ 11 = ?

132 ÷ 11 = ?

28 ÷ 4 = ?

64 ÷ 8 = ?

30 ÷ 6 = ?

9 ÷ 9 = ?

27 ÷ 3 = ?

70 ÷ 7 = ?

6 ÷ 2 = ?

48 ÷ 12 = ?

18 ÷ 3 = ?

Step 2 — cross out the sentence with each answer

1.The villain flies a giant pterodactyl over the fences, then scans the area with a stolen laser.

2.The villain marches a grumpy triceratops into town, then blasts a tree with a dna mutator ray.

3.The villain rides a fast raptor through the lab gates, then scans the area with a stolen laser.

4.The villain stomps a heavy stegosaurus down the path, then blasts a tree with a dna mutator ray.

5.The villain rides a fast raptor through the lab gates, then slips away using night vision goggles.

6.The villain stomps a heavy stegosaurus down the path, then tracks wild dinos with a thermal screen.

7.The villain leads a roaring t-rex past the cameras, then blasts a tree with a dna mutator ray.

8.The villain marches a grumpy triceratops into town, then blows a loud sonic whistle to escape.

9.The villain leads a roaring t-rex past the cameras, then scans the area with a stolen laser.

10.The villain flies a giant pterodactyl over the fences, then blasts a tree with a dna mutator ray.

11.The villain stomps a heavy stegosaurus down the path, then blows a loud sonic whistle to escape.

12.The villain marches a grumpy triceratops into town, then slips away using night vision goggles.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Great Dino Lab Mix-Up

Culprit: Alan Grant (Stomping a Stegosaurus · Sonic Dino Whistle · Right Handed Writer · Brown Pith Helmet · Tricked by Sweet Fruit)

Clue 1 (Place value): "THEY DO NOT HAVE A THERMAL DINO TRACKER"
What is the value of the 1 in 8,147? = 100 (T) · What is the value of the 5 in 158? = 50 (O) · What is the value of the 8 in 38,043? = 8000 (R) · What is the value of the 6 in 6,270? = 6000 (K) · What is the value of the 9 in 9,028? = 9000 (C) · What is the value of the 3 in 538? = 30 (A) · What is the value of the 3 in 9,377? = 300 (I) · What is the value of the 7 in 279? = 70 (L) · What is the value of the 2 in 327? = 20 (H) · What is the value of the 3 in 3,022? = 3000 (Y) · What is the value of the 5 in 560? = 500 (M) · What is the value of the 8 in 1,801? = 800 (V) · What is the value of the 1 in 1,087? = 1000 (E) · What is the value of the 8 in 3,989? = 80 (D) · What is the value of the 4 in 471? = 400 (N)
Clue 2 (Rounding): "THE SUSPECT WRITES ONLY WITH THEIR RIGHT HAND"
Round 286 to the nearest ten = 290 (T) · Round 4,292 to the nearest hundred = 4300 (N) · Round 8,543 to the nearest thousand = 9000 (I) · Round 169 to the nearest ten = 170 (G) · Round 53 to the nearest ten = 50 (L) · Round 658 to the nearest hundred = 700 (E) · Round 22 to the nearest ten = 20 (R) · Round 2,911 to the nearest hundred = 2900 (H) · Round 66 to the nearest ten = 70 (S) · Round 6,583 to the nearest thousand = 7000 (U) · Round 1,739 to the nearest hundred = 1700 (P) · Round 223 to the nearest hundred = 200 (Y) · Round 4,748 to the nearest thousand = 5000 (D) · Round 26 to the nearest ten = 30 (C) · Round 110 to the nearest ten = 110 (A) · Round 1,337 to the nearest hundred = 1300 (O) · Round 1,088 to the nearest hundred = 1100 (W)
Clue 3 (Addition): "THEY WILL ALWAYS STOP FOR SOME SWEET FRUIT"
2655 + 2085 = 4740 (T) · 6146 + 2657 = 8803 (H) · 1910 + 1446 = 3356 (P) · 3279 + 1699 = 4978 (S) · 2557 + 4520 = 7077 (L) · 1536 + 2118 = 3654 (O) · 4022 + 4640 = 8662 (M) · 3505 + 2480 = 5985 (R) · 3619 + 5507 = 9126 (Y) · 2933 + 1857 = 4790 (A) · 2348 + 2617 = 4965 (E) · 2211 + 3415 = 5626 (U) · 2088 + 2385 = 4473 (F) · 3500 + 2174 = 5674 (W) · 2608 + 2548 = 5156 (I)
Clue 4 (Subtraction): "THE SNEAKY THIEF DROPPED A BROWN PITH HELMET"
10164 - 1700 = 8464 (T) · 4259 - 112 = 4147 (Y) · 8093 - 3794 = 4299 (H) · 8593 - 4496 = 4097 (P) · 7621 - 4234 = 3387 (S) · 10600 - 4047 = 6553 (M) · 6890 - 873 = 6017 (D) · 8200 - 629 = 7571 (E) · 5913 - 1551 = 4362 (F) · 6626 - 3132 = 3494 (N) · 7425 - 549 = 6876 (W) · 12717 - 4248 = 8469 (A) · 9879 - 3169 = 6710 (K) · 9037 - 1422 = 7615 (I) · 4883 - 2500 = 2383 (R) · 10540 - 3591 = 6949 (B) · 10453 - 4139 = 6314 (O) · 7001 - 1018 = 5983 (L)
Clue 5 (Division facts (1-12)): surviving statement (box 11) → Alan Grant
22 ÷ 11 = 2 · 132 ÷ 11 = 12 · 28 ÷ 4 = 7 · 64 ÷ 8 = 8 · 30 ÷ 6 = 5 · 9 ÷ 9 = 1 · 27 ÷ 3 = 9 · 70 ÷ 7 = 10 · 6 ÷ 2 = 3 · 48 ÷ 12 = 4 · 18 ÷ 3 = 6

About this mystery

Grade level: Grade 4 math
Math topics: Place value, Rounding, Addition, Subtraction, Division
Reading level: grades 3-4
Theme: The Great Dino Lab Mix-Up — set in Dino Valley Research Lab
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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