🦕 DinosaursGrade 5Reading: grades 5-6Fractions of a numberOrder of operationsMultiplicationRoundingDivision
The Case of the Missing Fossil Core
A rare golden T-Rex tooth was taken from the Paleo Peak Lab! The thief left behind footprints, torn gear, and mysterious clues around the fossil digsite. Use your deduction skills and math clues to crack the case!
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 Stance | Dig Tool | Dominant Hand | Fossil Dust | Dino Distraction |
|---|---|---|---|---|---|
| Dr Alan Grant | Ankylosaurus Slam | Sonic Mapper | Left-Handed | Grey Clay Dust | Screeching Whistle |
| Karen Chin | Triceratops Charge | Chisel Drill | Left-Handed | Red Sand Dust | Roaring Speaker |
| Edward Drinker Cope | Stegosaurus Tail Whip | Laser Scanner | Left-Handed | Red Sand Dust | Bright Spotlight |
| Lindsay Zanno | Stegosaurus Tail Whip | Laser Scanner | Left-Handed | Red Sand Dust | Roaring Speaker |
| Lawrence Lambe | Velociraptor Dash | Plaster Mold | Left-Handed | Grey Clay Dust | Roaring Speaker |
| Xu Xing | Stegosaurus Tail Whip | Plaster Mold | Right-Handed | Red Sand Dust | Bright Spotlight |
| Rodolfo Coria | Ankylosaurus Slam | Laser Scanner | Right-Handed | Red Sand Dust | Roaring Speaker |
| Luis Chiappe | TRex Pounce | Magnifying Lens | Right-Handed | Grey Clay Dust | Screeching Whistle |
| Paul Barrett | TRex Pounce | Laser Scanner | Right-Handed | Yellow Chalk Dust | Bright Spotlight |
| Gideon Mantell | Stegosaurus Tail Whip | Chisel Drill | Left-Handed | Red Sand Dust | Bright Spotlight |
| Dr Ellie Sattler | Ankylosaurus Slam | Sonic Mapper | Left-Handed | Red Sand Dust | Roaring Speaker |
| Phil Currie | Stegosaurus Tail Whip | Plaster Mold | Left-Handed | Grey Clay Dust | Bright Spotlight |
| Jack Horner | Triceratops Charge | Plaster Mold | Right-Handed | Red Sand Dust | Bright Spotlight |
| Mary Anning | Ankylosaurus Slam | Chisel Drill | Right-Handed | Grey Clay Dust | Bright Spotlight |
| Dong Zhiming | TRex Pounce | Chisel Drill | Left-Handed | Red Sand Dust | Bright Spotlight |
| Nizar Ibrahim | Velociraptor Dash | Sonic Mapper | Left-Handed | Red Sand Dust | Bright Spotlight |
| Patricia Vickers Rich | Velociraptor Dash | Chisel Drill | Left-Handed | Yellow Chalk Dust | Bright Spotlight |
| Roy Chapman Andrews | TRex Pounce | Sonic Mapper | Right-Handed | Red Sand Dust | Bright Spotlight |
| Kristi Curry Rogers | Stegosaurus Tail Whip | Magnifying Lens | Left-Handed | Red Sand Dust | Bright Spotlight |
| Barnum Brown | Velociraptor Dash | Plaster Mold | Left-Handed | Yellow Chalk Dust | Roaring Speaker |
| Charles Knight | Stegosaurus Tail Whip | Sonic Mapper | Left-Handed | Grey Clay Dust | Bright Spotlight |
Clue 1
Fractions of a number
You examine the lab inventory log to see what fraction of the dig equipment was tampered with during the theft.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
T
6
12
23
5
26
9
9
33
26
36
7
14
23
37
36
14
T
6
3
37
23
33
2
33
19
36
26
30
15
26
36
19
9
23
36
37
3/10 of 20 =T
5/10 of 6 =U
1/5 of 25 =V
3/4 of 48 =N
3/6 of 14 =D
2/8 of 148 =S
5/10 of 66 =A
5/10 of 52 =I
1/2 of 4 =M
2/6 of 45 =Y
1/8 of 184 =E
2/6 of 36 =H
2/8 of 76 =G
3/6 of 18 =L
5/6 of 36 =F
1/3 of 42 =O
0/16 letters found
Clue 2
Order of operations
A scrambled security code on the fossil vault keypad requires solving multi-step calculations to unlock.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
N
55
76
72
44
13
76
76
41
7
7
14
76
28
72
14
44
7
29
7
59
44
57
72
9
7
50
44
11
72
14
46
N
55
70
44
70
49 + 3 × 2 =N
27 + 5 × 9 =T
3 × 9 - 20 =S
3 + 2 × 3 =I
30 + 4 × 4 =A
6 × 6 - 8 =W
10 × 4 - 11 =U
12 × 8 - 20 =O
6 × 11 - 9 =C
4 + 8 × 5 =E
9 × 7 - 4 =P
6 × 7 - 1 =K
30 + 5 × 8 =D
9 × 7 - 13 =L
7 × 5 - 24 =F
4 + 3 × 3 =B
5 + 3 × 3 =H
0/17 letters found
Clue 3
Multiplication facts (1-12)
You count the rows of fossil crates stacked inside the storage tent to trace the thiefs escape route.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
A
80
121
32
2
12
50
84
24
45
96
84
54
2
12
50
84
88
A
80
16
66
84
50
66
24
48
24
45
66
70
84
144
54
66
66
8 × 10 =A
7 × 10 =C
8 × 12 =O
11 × 8 =M
5 × 9 =P
12 × 12 =F
5 × 10 =H
11 × 6 =E
11 × 11 =B
2 × 1 =I
6 × 9 =L
2 × 8 =D
4 × 3 =G
4 × 8 =R
4 × 6 =S
4 × 12 =U
12 × 7 =T
0/17 letters found
Clue 4
Rounding
The digsite radar system only displays approximate distance readings rounded to the nearest hundred.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
B
130
900
900
290
170
20
700
2000
290
110
500
2300
20
2300
9000
900
4300
2300
20
2300
370
700
2000
20
2300
370
110
1300
2000
370
370
90
110
290
Round 131 to the nearest tenB
Round 18 to the nearest tenR
Round 2,325 to the nearest hundredE
Round 1,909 to the nearest thousandN
Round 291 to the nearest tenT
Round 8,894 to the nearest thousandC
Round 4,315 to the nearest hundredV
Round 167 to the nearest tenP
Round 871 to the nearest hundredO
Round 695 to the nearest hundredI
Round 88 to the nearest tenU
Round 374 to the nearest tenD
Round 1,323 to the nearest hundredA
Round 499 to the nearest hundredW
Round 112 to the nearest tenS
0/15 letters found
Clue 5
Division facts (1-12) — the last clue
To figure out how many supply bags were carried away you divide the total weight of missing equipment equally.
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
20 ÷ 10 = ?
21 ÷ 7 = ?
6 ÷ 1 = ?
36 ÷ 3 = ?
81 ÷ 9 = ?
7 ÷ 1 = ?
20 ÷ 5 = ?
50 ÷ 10 = ?
2 ÷ 2 = ?
55 ÷ 5 = ?
8 ÷ 1 = ?
Step 2 — cross out the sentence with each answer
1.The villain used velociraptor dash, then calibrated the laser scanner.
2.The villain swung stegosaurus tail whip, then revved the chisel drill.
3.The villain swung stegosaurus tail whip, then calibrated the laser scanner.
4.The villain executed trex pounce, then pinged the sonic mapper.
5.The villain triggered triceratops charge, then pinged the sonic mapper.
6.The villain used velociraptor dash, then pinged the sonic mapper.
7.The villain used velociraptor dash, then poured the plaster mold.
8.The villain delivered ankylosaurus slam, then poured the plaster mold.
9.The villain delivered ankylosaurus slam, then revved the chisel drill.
10.The villain executed trex pounce, then revved the chisel drill.
11.The villain executed trex pounce, then focused the magnifying lens.
12.The villain triggered triceratops charge, then calibrated the laser scanner.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Case of the Missing Fossil Core
Culprit: Dong Zhiming (TRex Pounce · Chisel Drill · Left-Handed · Red Sand Dust · Bright Spotlight)
- Clue 1 (Fractions of a number): "THE VILLAIN DOES NOT USE A MAGNIFYING LENS"3/10 of 20 = 6 (T) · 5/10 of 6 = 3 (U) · 1/5 of 25 = 5 (V) · 3/4 of 48 = 36 (N) · 3/6 of 14 = 7 (D) · 2/8 of 148 = 37 (S) · 5/10 of 66 = 33 (A) · 5/10 of 52 = 26 (I) · 1/2 of 4 = 2 (M) · 2/6 of 45 = 15 (Y) · 1/8 of 184 = 23 (E) · 2/6 of 36 = 12 (H) · 2/8 of 76 = 19 (G) · 3/6 of 18 = 9 (L) · 5/6 of 36 = 30 (F) · 1/3 of 42 = 14 (O)
- Clue 2 (Order of operations): "NOTEBOOKS SHOW THE SUSPECT IS LEFT HANDED"49 + 3 × 2 = 55 (N) · 27 + 5 × 9 = 72 (T) · 3 × 9 - 20 = 7 (S) · 3 + 2 × 3 = 9 (I) · 30 + 4 × 4 = 46 (A) · 6 × 6 - 8 = 28 (W) · 10 × 4 - 11 = 29 (U) · 12 × 8 - 20 = 76 (O) · 6 × 11 - 9 = 57 (C) · 4 + 8 × 5 = 44 (E) · 9 × 7 - 4 = 59 (P) · 6 × 7 - 1 = 41 (K) · 30 + 5 × 8 = 70 (D) · 9 × 7 - 13 = 50 (L) · 7 × 5 - 24 = 11 (F) · 4 + 3 × 3 = 13 (B) · 5 + 3 × 3 = 14 (H)
- Clue 3 (Multiplication facts (1-12)): "A BRIGHT SPOTLIGHT MADE THE SUSPECT FLEE"8 × 10 = 80 (A) · 7 × 10 = 70 (C) · 8 × 12 = 96 (O) · 11 × 8 = 88 (M) · 5 × 9 = 45 (P) · 12 × 12 = 144 (F) · 5 × 10 = 50 (H) · 11 × 6 = 66 (E) · 11 × 11 = 121 (B) · 2 × 1 = 2 (I) · 6 × 9 = 54 (L) · 2 × 8 = 16 (D) · 4 × 3 = 12 (G) · 4 × 8 = 32 (R) · 4 × 6 = 24 (S) · 4 × 12 = 48 (U) · 12 × 7 = 84 (T)
- Clue 4 (Rounding): "BOOT PRINTS WERE COVERED IN RED SAND DUST"Round 131 to the nearest ten = 130 (B) · Round 18 to the nearest ten = 20 (R) · Round 2,325 to the nearest hundred = 2300 (E) · Round 1,909 to the nearest thousand = 2000 (N) · Round 291 to the nearest ten = 290 (T) · Round 8,894 to the nearest thousand = 9000 (C) · Round 4,315 to the nearest hundred = 4300 (V) · Round 167 to the nearest ten = 170 (P) · Round 871 to the nearest hundred = 900 (O) · Round 695 to the nearest hundred = 700 (I) · Round 88 to the nearest ten = 90 (U) · Round 374 to the nearest ten = 370 (D) · Round 1,323 to the nearest hundred = 1300 (A) · Round 499 to the nearest hundred = 500 (W) · Round 112 to the nearest ten = 110 (S)
- Clue 5 (Division facts (1-12)): surviving statement (box 10) → Dong Zhiming20 ÷ 10 = 2 · 21 ÷ 7 = 3 · 6 ÷ 1 = 6 · 36 ÷ 3 = 12 · 81 ÷ 9 = 9 · 7 ÷ 1 = 7 · 20 ÷ 5 = 4 · 50 ÷ 10 = 5 · 2 ÷ 2 = 1 · 55 ÷ 5 = 11 · 8 ÷ 1 = 8
About this mystery
- Grade level
- Grade 5 math
- Math topics
- Fractions of a number, Order of operations, Multiplication, Rounding, Division
- Reading level
- grades 5-6
- Theme
- The Case of the Missing Fossil Core — set in Palaeo Peak Digsite Lab
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects