Grade 10Reading: grades 7-9Place valueAdditionSubtractionMultiplicationDivision
The Echo Canyon Astrolabe Heist
The golden astrolabe has been stolen from the expedition camp deep inside Echo Canyon! A thief disguised as a camp member took the artifact and fled into the ruins. We must examine the clues left behind to unmask the Phantom Raider before they escape the canyon canyon.
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 | Primary Gear | Special Skill | Handedness | Hair Style | Hidden Flaw |
|---|---|---|---|---|---|
| Sallie Chipman | laser cutter | climbing spikes | right-handed | blonde ponytail | ticklish feet |
| Lewis Clark | drone scout | zip line pulley | right-handed | blonde ponytail | allergic to pollen |
| Percy Fawcett | smoke bombs | jetpack boots | right-handed | shaved head | allergic to pollen |
| Amelia Earhart | grappling hook | night vision goggles | right-handed | shaved head | allergic to pollen |
| Ibn Battuta | drone scout | night vision goggles | right-handed | shaved head | allergic to pollen |
| Matthew Henson | smoke bombs | night vision goggles | right-handed | blonde ponytail | fear of heights |
| Sacagawea | drone scout | jetpack boots | left-handed | blonde ponytail | ticklish feet |
| Jeanne Baret | grappling hook | sonar radar | left-handed | blonde ponytail | fear of heights |
| Steve Irwin | decoy hologram | sonar radar | right-handed | spiky black hair | fear of heights |
| Gertrude Bell | decoy hologram | jetpack boots | right-handed | blonde ponytail | allergic to pollen |
| Marco Polo | smoke bombs | sonar radar | left-handed | shaved head | ticklish feet |
| Mary Kingsley | smoke bombs | night vision goggles | right-handed | blonde ponytail | allergic to pollen |
| Lara Croft | decoy hologram | climbing spikes | left-handed | blonde ponytail | allergic to pollen |
| Nathan Drake | drone scout | climbing spikes | left-handed | spiky black hair | ticklish feet |
| Harriet Quimby | grappling hook | sonar radar | right-handed | blonde ponytail | allergic to pollen |
| Charles Lindbergh | laser cutter | night vision goggles | right-handed | blonde ponytail | allergic to pollen |
| Freya Stark | smoke bombs | zip line pulley | left-handed | spiky black hair | fear of heights |
| Evander Yale | smoke bombs | climbing spikes | right-handed | shaved head | allergic to pollen |
| Robert Peary | decoy hologram | night vision goggles | right-handed | blonde ponytail | ticklish feet |
| Jacques Cousteau | laser cutter | jetpack boots | right-handed | blonde ponytail | ticklish feet |
| Roald Amundsen | smoke bombs | jetpack boots | left-handed | blonde ponytail | ticklish feet |
Clue 1
Place value
An ancient combination lock blocks the vault door. By studying the digit positions of the passcode, you reveal a major secret about the Raider's gear.
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
50
500
20
4000
8000
100
100
2000
8000
10
700
90
20
300
10
90
T
50
200
300
20
300
90
10
2000
60
60
2000
700
2000
60
What is the value of the 5 in 189,054?T
What is the value of the 2 in 42,511?A
What is the value of the 7 in 54,762?D
What is the value of the 3 in 710,370?S
What is the value of the 9 in 28,497?O
What is the value of the 8 in 538,596?I
What is the value of the 6 in 14,068?R
What is the value of the 2 in 575,829?E
What is the value of the 2 in 39,297?U
What is the value of the 4 in 54,135?V
What is the value of the 5 in 61,546?H
What is the value of the 1 in 56,145?L
What is the value of the 1 in 98,919?N
0/13 letters found
Clue 2
Addition
To track the suspect's movements, you add up the total weight of the discarded supplies found near the rope bridge.
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
2366
7969
6552
T
2366
7969
5856
6552
8713
8037
6552
9136
4315
6552
3600
5218
5856
7592
7969
T
2366
7969
9136
9248
3298
6552
3298
3600
9709
4021
3298
7592
6552
3600
987 + 1379 =T
1607 + 1691 =D
2298 + 1723 =U
2487 + 1828 =V
2448 + 3408 =I
5327 + 3809 =A
2980 + 6729 =M
2524 + 5068 =G
3910 + 5338 =N
2474 + 5563 =L
1929 + 3289 =R
4125 + 2427 =E
2256 + 1344 =S
3340 + 4629 =H
4050 + 4663 =F
0/15 letters found
Clue 3
Subtraction
You calculate the missing fuel units from the generator to figure out exactly how long the suspect had to hide.
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
5017
6829
6360
2455
3170
8864
1422
6360
2455
8191
1717
6360
6360
7585
6360
8191
1717
6360
3170
2455
8191
8869
2455
8864
1717
1243
1776
1557
1181
5339
6360
2455
8191
9200 - 4183 =T
1562 - 381 =O
5312 - 3755 =L
6279 - 3109 =A
12375 - 4790 =Z
3087 - 1370 =N
12083 - 3214 =P
7143 - 4688 =R
10517 - 1653 =I
8359 - 168 =S
3295 - 2052 =G
9250 - 3911 =W
3054 - 1632 =D
4041 - 2265 =F
8362 - 1533 =H
10261 - 3901 =E
0/16 letters found
Clue 4
Multiplication facts (1-12)
By multiplying the rows of ancient floor tiles that were stepped on, you map out the suspect's path through the pressure-plate room.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
G
14
10
7
40
88
32
110
100
27
132
32
40
110
10
28
5
132
54
27
9
88
27
88
7
88
28
100
15
88
5
54
32
40
2 × 7 =G
5 × 3 =B
1 × 9 =W
4 × 8 =N
7 × 4 =F
11 × 12 =A
1 × 7 =L
11 × 10 =S
10 × 10 =T
5 × 8 =D
1 × 10 =O
3 × 9 =R
6 × 9 =I
11 × 8 =E
1 × 5 =H
0/15 letters found
Clue 5
Division facts (1-12) — the last clue
To find the escape route, you divide the map coordinates equally among your scout team to search the canyon grid.
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
48 ÷ 12 = ?
24 ÷ 2 = ?
6 ÷ 6 = ?
10 ÷ 1 = ?
56 ÷ 8 = ?
4 ÷ 2 = ?
55 ÷ 11 = ?
72 ÷ 8 = ?
54 ÷ 9 = ?
24 ÷ 3 = ?
30 ÷ 10 = ?
Step 2 — cross out the sentence with each answer
1.The villain vanishes in a puff of silver smoke, then navigates the dark tunnels with ease.
2.The villain swings across the canyon vault, then navigates the dark tunnels with ease.
3.The villain slices open the reinforced metal door, then scales the sheer cliffside.
4.The villain creates a flickering double of themselves, then hovers safely over the spike pits.
5.The villain slices open the reinforced metal door, then slides down the steel cables.
6.The villain swings across the canyon vault, then slides down the steel cables.
7.The villain slices open the reinforced metal door, then hovers safely over the spike pits.
8.The villain vanishes in a puff of silver smoke, then slides down the steel cables.
9.The villain creates a flickering double of themselves, then pings the entire cavern for loot.
10.The villain swings across the canyon vault, then scales the sheer cliffside.
11.The villain slices open the reinforced metal door, then navigates the dark tunnels with ease.
12.The villain sends a tiny quadcopter to scout ahead, then slides down the steel cables.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Echo Canyon Astrolabe Heist
Culprit: Charles Lindbergh (laser cutter · night vision goggles · right-handed · blonde ponytail · allergic to pollen)
- Clue 1 (Place value): "THE VILLAIN DOES NOT USE SONAR RADAR"What is the value of the 5 in 189,054? = 50 (T) · What is the value of the 2 in 42,511? = 2000 (A) · What is the value of the 7 in 54,762? = 700 (D) · What is the value of the 3 in 710,370? = 300 (S) · What is the value of the 9 in 28,497? = 90 (O) · What is the value of the 8 in 538,596? = 8000 (I) · What is the value of the 6 in 14,068? = 60 (R) · What is the value of the 2 in 575,829? = 20 (E) · What is the value of the 2 in 39,297? = 200 (U) · What is the value of the 4 in 54,135? = 4000 (V) · What is the value of the 5 in 61,546? = 500 (H) · What is the value of the 1 in 56,145? = 100 (L) · What is the value of the 1 in 98,919? = 10 (N)
- Clue 2 (Addition): "THE THIEF LEAVES RIGHT HANDED SMUDGES"987 + 1379 = 2366 (T) · 1607 + 1691 = 3298 (D) · 2298 + 1723 = 4021 (U) · 2487 + 1828 = 4315 (V) · 2448 + 3408 = 5856 (I) · 5327 + 3809 = 9136 (A) · 2980 + 6729 = 9709 (M) · 2524 + 5068 = 7592 (G) · 3910 + 5338 = 9248 (N) · 2474 + 5563 = 8037 (L) · 1929 + 3289 = 5218 (R) · 4125 + 2427 = 6552 (E) · 2256 + 1344 = 3600 (S) · 3340 + 4629 = 7969 (H) · 4050 + 4663 = 8713 (F)
- Clue 3 (Subtraction): "THE RAIDER SNEEZES NEAR SPRING FLOWERS"9200 - 4183 = 5017 (T) · 1562 - 381 = 1181 (O) · 5312 - 3755 = 1557 (L) · 6279 - 3109 = 3170 (A) · 12375 - 4790 = 7585 (Z) · 3087 - 1370 = 1717 (N) · 12083 - 3214 = 8869 (P) · 7143 - 4688 = 2455 (R) · 10517 - 1653 = 8864 (I) · 8359 - 168 = 8191 (S) · 3295 - 2052 = 1243 (G) · 9250 - 3911 = 5339 (W) · 3054 - 1632 = 1422 (D) · 4041 - 2265 = 1776 (F) · 8362 - 1533 = 6829 (H) · 10261 - 3901 = 6360 (E)
- Clue 4 (Multiplication facts (1-12)): "GOLDEN STRANDS OF HAIR WERE LEFT BEHIND"2 × 7 = 14 (G) · 5 × 3 = 15 (B) · 1 × 9 = 9 (W) · 4 × 8 = 32 (N) · 7 × 4 = 28 (F) · 11 × 12 = 132 (A) · 1 × 7 = 7 (L) · 11 × 10 = 110 (S) · 10 × 10 = 100 (T) · 5 × 8 = 40 (D) · 1 × 10 = 10 (O) · 3 × 9 = 27 (R) · 6 × 9 = 54 (I) · 11 × 8 = 88 (E) · 1 × 5 = 5 (H)
- Clue 5 (Division facts (1-12)): surviving statement (box 11) → Charles Lindbergh48 ÷ 12 = 4 · 24 ÷ 2 = 12 · 6 ÷ 6 = 1 · 10 ÷ 1 = 10 · 56 ÷ 8 = 7 · 4 ÷ 2 = 2 · 55 ÷ 11 = 5 · 72 ÷ 8 = 9 · 54 ÷ 9 = 6 · 24 ÷ 3 = 8 · 30 ÷ 10 = 3
About this mystery
- Grade level
- Grade 10 math
- Math topics
- Place value, Addition, Subtraction, Multiplication, Division
- Reading level
- grades 7-9
- Theme
- The Echo Canyon Astrolabe Heist — set in The ancient stone temples of Echo Canyon
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects