🔎 ManateesGrade 7Reading: grades 7-9IntegersPercentagesOrder of operationsExponentsTwo-step equations
The Sanctuary Seagrass Mystery
Someone tampered with the hydrophones and stole the fresh seagrass supplies meant for rescued manatees. Detective, examine the clues and track down the suspect.
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 Gadget | Marine Gear | Dominant Hand | Headgear Trail | Deterrent |
|---|---|---|---|---|---|
| Marina Vega | Water Jet Pack | Neoprene Suit | Left Handed | Silver Hair Clip | Seagrass Snack |
| Victor Cruz | Sonar Tracker | Kevlar Fins | Left Handed | Silver Hair Clip | Acoustic Whistle |
| Grace Hopper | Sonar Tracker | Kevlar Fins | Left Handed | Silver Hair Clip | Seagrass Snack |
| Captain Jonah Reed | Submersible Drone | Turbo Scooter | Left Handed | Braided Paracord | Warm Water Spray |
| Felix Dupont | Thermal Scanner | Kevlar Fins | Left Handed | Silver Hair Clip | Warm Water Spray |
| Derek Brooks | Thermal Scanner | Turbo Scooter | Left Handed | Silver Hair Clip | Warm Water Spray |
| Kai Tani | Thermal Scanner | Turbo Scooter | Left Handed | Silver Hair Clip | Seagrass Snack |
| Hugo Morales | Thermal Scanner | Mesh Harvester | Right Handed | Braided Paracord | Warm Water Spray |
| Elena Rostova | Water Jet Pack | Mesh Harvester | Left Handed | Neon Snorkel Strap | Acoustic Whistle |
| Tessa Wright | Hydrophone Array | Mesh Harvester | Left Handed | Silver Hair Clip | Warm Water Spray |
| Marcus Vance | Thermal Scanner | Dive Beacon | Left Handed | Braided Paracord | Seagrass Snack |
| Olivia Chen | Water Jet Pack | Kevlar Fins | Left Handed | Silver Hair Clip | Warm Water Spray |
| Leo Sterling | Submersible Drone | Kevlar Fins | Right Handed | Neon Snorkel Strap | Acoustic Whistle |
| Hannah Abbott | Submersible Drone | Mesh Harvester | Left Handed | Silver Hair Clip | Warm Water Spray |
| Samira Khan | Thermal Scanner | Mesh Harvester | Left Handed | Neon Snorkel Strap | Seagrass Snack |
| Aisha Patel | Sonar Tracker | Turbo Scooter | Right Handed | Silver Hair Clip | Warm Water Spray |
| Sarah Jenkins | Hydrophone Array | Neoprene Suit | Right Handed | Silver Hair Clip | Acoustic Whistle |
| Dylan Mercer | Thermal Scanner | Neoprene Suit | Left Handed | Silver Hair Clip | Warm Water Spray |
| Naomi Nagata | Sonar Tracker | Dive Beacon | Left Handed | Braided Paracord | Warm Water Spray |
| Dr Maya Lin | Thermal Scanner | Mesh Harvester | Left Handed | Silver Hair Clip | Seagrass Snack |
| Julian Ross | Water Jet Pack | Neoprene Suit | Left Handed | Neon Snorkel Strap | Warm Water Spray |
Clue 1
Integers
The temperature logs in the manatee rehabilitation pool registered sudden positive and negative shifts during the breach.
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
21
19
28
26
8
20
3
T
21
28
10
13
12
16
12
15
3
T
21
10
26
28
8
1
28
26
19
19
8
13
29
28
26
T
21
28
13
8 - (-13) =T
(-13) + 16 =O
8 - (-8) =I
(-5) + 20 =N
(-10) + 39 =V
(-15) + 16 =M
(-15) + 28 =R
(-2) + 22 =B
(-4) + 14 =U
(-11) + 19 =A
11 - (-15) =S
(-14) + 26 =D
(-11) + 39 =E
5 - (-14) =H
0/14 letters found
Clue 2
Percentages
A digital tally of the missing seagrass bundles showed precise percentage drop-offs across three storage bays.
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
11
26
33
22
29
22
37
33
36
T
11
55
15
31
T
11
33
22
1
34
32
22
55
31
T
11
26
T
11
26
33
31
15
1
33
8
T
11
26
25
2
51
50% of 22 =T
25% of 100 =A
40% of 80 =G
50% of 52 =H
20% of 170 =O
10% of 220 =S
10% of 310 =I
5% of 160 =F
10% of 150 =R
10% of 510 =D
25% of 148 =P
20% of 275 =W
75% of 48 =C
5% of 580 =U
25% of 4 =L
5% of 40 =N
60% of 55 =E
0/17 letters found
Clue 3
Order of operations
The automated hydrophone diagnostic grid processed sensor equations using strict mathematical priority to pinpoint signals.
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
69
25
45
12
78
97
102
T
69
45
119
67
67
45
T
69
67
45
78
T
69
45
49
84
67
102
116
38
78
67
116
38
78
T
69
45
67
12
114
67
78
89
53 + 8 × 2 =T
10 × 11 - 21 =Y
37 + 6 × 2 =D
12 × 9 - 11 =B
3 × 6 - 6 =S
11 × 9 - 15 =F
8 × 6 - 10 =W
12 × 6 - 5 =R
10 + 7 × 5 =E
75 + 3 × 9 =O
7 + 9 × 2 =H
12 × 10 - 4 =M
12 × 10 - 1 =U
12 × 12 - 30 =P
68 + 2 × 5 =A
0/15 letters found
Clue 4
Exponents
Data rates from the underwater tracking beacons multiplied exponentially as the intruder fled through the canal.
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
125
81
324
343
16
289
81
343
144
25
361
49
324
A
125
343
49
225
144
343
128
216
A
125
81
169
49
64
128
128
361
169
16
361
A
125
49
32
289
5^3 =A
12^2 =L
15^2 =C
7^3 =I
2^7 =P
13^2 =D
7^2 =R
5^2 =V
4^2 =N
2^5 =B
3^4 =S
6^3 =W
17^2 =Y
18^2 =H
19^2 =E
2^6 =O
0/16 letters found
Clue 5
Two-step equations — the last clue
Analyzing the pressure readings in the main water valve required solving a two-step formula to uncover hidden location coordinates.
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
6x + 12 = 54, x = ?
6x + 1 = 55, x = ?
4x + 6 = 54, x = ?
5x + 5 = 55, x = ?
3x + 2 = 26, x = ?
5x + 1 = 16, x = ?
3x + 3 = 15, x = ?
2x + 1 = 11, x = ?
4x + 2 = 46, x = ?
6x + 10 = 46, x = ?
2x + 8 = 12, x = ?
Step 2 — cross out the sentence with each answer
1.The villain scanned with the thermal scanner, then zipped up the neoprene suit.
2.The villain deployed the submersible drone, then loaded the mesh harvester.
3.The villain activated the sonar tracker, then strapped on the kevlar fins.
4.The villain fired up the water jet pack, then switched on the dive beacon.
5.The villain fired up the water jet pack, then loaded the mesh harvester.
6.The villain deployed the submersible drone, then switched on the dive beacon.
7.The villain scanned with the thermal scanner, then strapped on the kevlar fins.
8.The villain activated the sonar tracker, then revved the turbo scooter.
9.The villain fired up the water jet pack, then strapped on the kevlar fins.
10.The villain rigged the hydrophone array, then revved the turbo scooter.
11.The villain activated the sonar tracker, then zipped up the neoprene suit.
12.The villain scanned with the thermal scanner, then revved the turbo scooter.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Sanctuary Seagrass Mystery
Culprit: Dylan Mercer (Thermal Scanner · Neoprene Suit · Left Handed · Silver Hair Clip · Warm Water Spray)
- Clue 1 (Integers): "THE SABOTEUR DID NOT USE A MESH HARVESTER"8 - (-13) = 21 (T) · (-13) + 16 = 3 (O) · 8 - (-8) = 16 (I) · (-5) + 20 = 15 (N) · (-10) + 39 = 29 (V) · (-15) + 16 = 1 (M) · (-15) + 28 = 13 (R) · (-2) + 22 = 20 (B) · (-4) + 14 = 10 (U) · (-11) + 19 = 8 (A) · 11 - (-15) = 26 (S) · (-14) + 26 = 12 (D) · (-11) + 39 = 28 (E) · 5 - (-14) = 19 (H)
- Clue 2 (Percentages): "THE SUSPECT WRITES LOGS WITH THEIR LEFT HAND"50% of 22 = 11 (T) · 25% of 100 = 25 (A) · 40% of 80 = 32 (G) · 50% of 52 = 26 (H) · 20% of 170 = 34 (O) · 10% of 220 = 22 (S) · 10% of 310 = 31 (I) · 5% of 160 = 8 (F) · 10% of 150 = 15 (R) · 10% of 510 = 51 (D) · 25% of 148 = 37 (P) · 20% of 275 = 55 (W) · 75% of 48 = 36 (C) · 5% of 580 = 29 (U) · 25% of 4 = 1 (L) · 5% of 40 = 2 (N) · 60% of 55 = 33 (E)
- Clue 3 (Order of operations): "THE SABOTEUR RETREATED FROM WARM WATER SPRAY"53 + 8 × 2 = 69 (T) · 10 × 11 - 21 = 89 (Y) · 37 + 6 × 2 = 49 (D) · 12 × 9 - 11 = 97 (B) · 3 × 6 - 6 = 12 (S) · 11 × 9 - 15 = 84 (F) · 8 × 6 - 10 = 38 (W) · 12 × 6 - 5 = 67 (R) · 10 + 7 × 5 = 45 (E) · 75 + 3 × 9 = 102 (O) · 7 + 9 × 2 = 25 (H) · 12 × 10 - 4 = 116 (M) · 12 × 10 - 1 = 119 (U) · 12 × 12 - 30 = 114 (P) · 68 + 2 × 5 = 78 (A)
- Clue 4 (Exponents): "A SHINY SILVER HAIR CLIP WAS DROPPED NEAR BY"5^3 = 125 (A) · 12^2 = 144 (L) · 15^2 = 225 (C) · 7^3 = 343 (I) · 2^7 = 128 (P) · 13^2 = 169 (D) · 7^2 = 49 (R) · 5^2 = 25 (V) · 4^2 = 16 (N) · 2^5 = 32 (B) · 3^4 = 81 (S) · 6^3 = 216 (W) · 17^2 = 289 (Y) · 18^2 = 324 (H) · 19^2 = 361 (E) · 2^6 = 64 (O)
- Clue 5 (Two-step equations): surviving statement (box 1) → Dylan Mercer6x + 12 = 54, x = 7 · 6x + 1 = 55, x = 9 · 4x + 6 = 54, x = 12 · 5x + 5 = 55, x = 10 · 3x + 2 = 26, x = 8 · 5x + 1 = 16, x = 3 · 3x + 3 = 15, x = 4 · 2x + 1 = 11, x = 5 · 4x + 2 = 46, x = 11 · 6x + 10 = 46, x = 6 · 2x + 8 = 12, x = 2
About this mystery
- Grade level
- Grade 7 math
- Math topics
- Integers, Percentages, Order of operations, Exponents, Two-step equations
- Reading level
- grades 7-9
- Theme
- The Sanctuary Seagrass Mystery — set in Crystal Cove Marine Sanctuary
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects