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Grade 7Reading: grades 7-9IntegersPercentagesOrder of operationsExponentsTwo-step equations

The Subzero Cipher

An elite rogue agent has infiltrated the Vanguard Academy's high-security mainframe. They bypassed the security grids to download the highly classified Omega Files, leaving the Chief Cryptographer locked in a digital holding cell. Your mission is to crack the clues, analyze the data, and unmask the saboteur before they slip off-grid.

Suspects

Possible suspects

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

21 of 21 still in play
NameSpecialist Spy SkillSpecial GadgetDominant Writing HandHair Dye AccentSecurity Vulnerability
James BondDisguise ArtistryEMP GrenadesLeft-handed writerSpiky silver dyeMagnetic floor panels
Kim PossibleDrone PilotingEMP GrenadesRight-handed writerNeon blue streaksSiren frequency jammer
Jason BourneLaser HackingJetpack BootsLeft-handed writerCopper orange buzzMagnetic floor panels
Alex RiderLaser HackingSonar VisorLeft-handed writerNeon blue streaksMagnetic floor panels
Ethan HuntParkour MasteryHologram ProjectorLeft-handed writerSpiky silver dyeMagnetic floor panels
Artemis FowlDrone PilotingGrappling WatchLeft-handed writerSpiky silver dyeSticky foam traps
Austin PowersCryptanalysisHologram ProjectorLeft-handed writerSpiky silver dyeMagnetic floor panels
Frank HardyParkour MasterySonar VisorLeft-handed writerNeon blue streaksSiren frequency jammer
John WatsonCryptanalysisHologram ProjectorRight-handed writerSpiky silver dyeMagnetic floor panels
Juni CortezDrone PilotingJetpack BootsRight-handed writerCopper orange buzzSiren frequency jammer
Carmen CortezDrone PilotingHologram ProjectorRight-handed writerSpiky silver dyeMagnetic floor panels
Nancy DrewLaser HackingJetpack BootsLeft-handed writerSpiky silver dyeMagnetic floor panels
Sherlock HolmesDisguise ArtistryHologram ProjectorLeft-handed writerCopper orange buzzMagnetic floor panels
Bruce WayneLaser HackingSonar VisorRight-handed writerCopper orange buzzSiren frequency jammer
Peter ParkerParkour MasteryGrappling WatchLeft-handed writerCopper orange buzzMagnetic floor panels
Katniss EverdeenLaser HackingGrappling WatchLeft-handed writerSpiky silver dyeMagnetic floor panels
Sydney BristowDisguise ArtistryGrappling WatchRight-handed writerSpiky silver dyeSiren frequency jammer
Joe HardyCryptanalysisJetpack BootsLeft-handed writerSpiky silver dyeSiren frequency jammer
Cody BanksParkour MasteryEMP GrenadesRight-handed writerNeon blue streaksSiren frequency jammer
Natasha RomanoffDisguise ArtistryEMP GrenadesRight-handed writerSpiky silver dyeSiren frequency jammer
Perry PlatypusCryptanalysisGrappling WatchLeft-handed writerCopper orange buzzSiren frequency jammer
Clue 1

Integers

The rogue cadet took the express elevator deep underground. By tracking the sequence of elevator trips across subterranean levels, we can calculate the final sub-level where they breached the firewall.

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
20
28
15
T
20
28
14
15
18
29
17
15
16
27
17
T
20
17
21
27
12
15
T
20
22
23
13
4
25
17
17
T
20
16
(-5) + 25 =T
7 - (-7) =I
(-15) + 19 =K
(-14) + 32 =F
23 - (-5) =H
(-7) + 34 =N
(-8) + 24 =S
11 - (-12) =A
(-3) + 25 =P
5 - (-10) =E
(-13) + 26 =C
(-7) + 36 =D
(-8) + 25 =O
(-9) + 21 =J
(-4) + 29 =B
(-1) + 22 =W
0/16 letters found
Clue 2

Percentages

We analyzed the stolen data packets left on the terminal screen. Finding the percentage of the remaining decryption buffer gives us the exact hardware signature of the thief's decryptor.

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
29
21
10
45
30
T
29
10
52
58
47
24
10
45
45
10
9
52
35
T
29
21
T
29
21
10
50
10
27
T
29
21
58
45
9
25% of 116 =T
25% of 200 =L
5% of 940 =S
5% of 700 =I
50% of 104 =W
60% of 50 =O
5% of 540 =F
5% of 480 =P
5% of 420 =H
50% of 116 =A
50% of 20 =E
25% of 36 =D
20% of 225 =N
0/13 letters found
Clue 3

Order of operations

To bypass the high-energy security barrier, the culprit had to input a specific mathematical sequence. Solving the complex expression in the correct order reveals the sequence they used.

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
74
50
28
114
57
28
105
T
74
T
74
31
17
57
57
28
31
28
120
T
74
50
28
36
114
57
105
28
T
74
27
46 + 4 × 7 =T
18 + 2 × 9 =M
16 + 3 × 4 =E
25 + 2 × 3 =R
6 × 9 - 4 =H
84 + 4 × 9 =D
3 + 9 × 6 =G
96 + 6 × 3 =A
95 + 5 × 2 =N
7 + 2 × 5 =I
4 × 8 - 5 =S
0/11 letters found
Clue 4

Exponents

The escape pod's tracking beacon sends an exponentially multiplying signal to hide its trail. Calculating the signal strength at the target power level points directly to the flight 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.

S
81
361
343
32
25
144
243
16
361
144
324
16
S
81
343
25
400
8
16
8
8
243
25
4
121
100
S
81
121
343
25
3^4 =S
18^2 =W
4^2 =A
2^2 =C
20^2 =F
7^3 =L
5^2 =E
12^2 =R
19^2 =I
3^5 =H
2^5 =V
2^3 =T
11^2 =O
10^2 =N
0/14 letters found
Clue 5

Two-step equations — the last clue

The getaway vehicle's weight limit had to be perfectly balanced with stolen gear. Solve for the unknown gadget payload variable to find the culprit's exact equipment weight.

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
3x + 12 = 27, x = ?
3x + 10 = 40, x = ?
3x + 12 = 21, x = ?
6x + 10 = 46, x = ?
6x + 11 = 53, x = ?
3x + 2 = 26, x = ?
6x + 3 = 15, x = ?
6x + 3 = 9, x = ?
6x + 7 = 73, x = ?
4x + 1 = 17, x = ?
4x + 4 = 52, x = ?
Step 2 — cross out the sentence with each answer
1.The villain scaled the outer ventilation shaft, then escaped using a grappling watch.
2.The villain bypassed the security lasers, then distracted the backup team with a hologram.
3.The villain cracked the encrypted mainframe, then distracted the backup team with a hologram.
4.The villain bypassed the security lasers, then disabled the cameras with EMP grenades.
5.The villain bypassed the security lasers, then escaped using a grappling watch.
6.The villain bypassed the security lasers, then mapped out the dark tunnels with a sonar visor.
7.The villain scaled the outer ventilation shaft, then mapped out the dark tunnels with a sonar visor.
8.The villain cracked the encrypted mainframe, then disabled the cameras with EMP grenades.
9.The villain scaled the outer ventilation shaft, then distracted the backup team with a hologram.
10.The villain fooled the guards with a mask, then disabled the cameras with EMP grenades.
11.The villain guided a mini-uav through the vents, then blasted away using jetpack boots.
12.The villain guided a mini-uav through the vents, then escaped using a grappling watch.
Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Subzero Cipher

Culprit: Ethan Hunt (Parkour Mastery · Hologram Projector · Left-handed writer · Spiky silver dye · Magnetic floor panels)
  1. Clue 1 (Integers): "THE THIEF DOES NOT OWN JETPACK BOOTS"
    (-5) + 25 = 20 (T) · 7 - (-7) = 14 (I) · (-15) + 19 = 4 (K) · (-14) + 32 = 18 (F) · 23 - (-5) = 28 (H) · (-7) + 34 = 27 (N) · (-8) + 24 = 16 (S) · 11 - (-12) = 23 (A) · (-3) + 25 = 22 (P) · 5 - (-10) = 15 (E) · (-13) + 26 = 13 (C) · (-7) + 36 = 29 (D) · (-8) + 25 = 17 (O) · (-9) + 21 = 12 (J) · (-4) + 29 = 25 (B) · (-1) + 22 = 21 (W)
  2. Clue 2 (Percentages): "THE NOTE WAS PENNED WITH THE LEFT HAND"
    25% of 116 = 29 (T) · 25% of 200 = 50 (L) · 5% of 940 = 47 (S) · 5% of 700 = 35 (I) · 50% of 104 = 52 (W) · 60% of 50 = 30 (O) · 5% of 540 = 27 (F) · 5% of 480 = 24 (P) · 5% of 420 = 21 (H) · 50% of 116 = 58 (A) · 50% of 20 = 10 (E) · 25% of 36 = 9 (D) · 20% of 225 = 45 (N)
  3. Clue 3 (Order of operations): "THE AGENT TRIGGERED THE MAGNETS"
    46 + 4 × 7 = 74 (T) · 18 + 2 × 9 = 36 (M) · 16 + 3 × 4 = 28 (E) · 25 + 2 × 3 = 31 (R) · 6 × 9 - 4 = 50 (H) · 84 + 4 × 9 = 120 (D) · 3 + 9 × 6 = 57 (G) · 96 + 6 × 3 = 114 (A) · 95 + 5 × 2 = 105 (N) · 7 + 2 × 5 = 17 (I) · 4 × 8 - 5 = 27 (S)
  4. Clue 4 (Exponents): "SILVER HAIR WAS LEFT AT THE CONSOLE"
    3^4 = 81 (S) · 18^2 = 324 (W) · 4^2 = 16 (A) · 2^2 = 4 (C) · 20^2 = 400 (F) · 7^3 = 343 (L) · 5^2 = 25 (E) · 12^2 = 144 (R) · 19^2 = 361 (I) · 3^5 = 243 (H) · 2^5 = 32 (V) · 2^3 = 8 (T) · 11^2 = 121 (O) · 10^2 = 100 (N)
  5. Clue 5 (Two-step equations): surviving statement (box 9) → Ethan Hunt
    3x + 12 = 27, x = 5 · 3x + 10 = 40, x = 10 · 3x + 12 = 21, x = 3 · 6x + 10 = 46, x = 6 · 6x + 11 = 53, x = 7 · 3x + 2 = 26, x = 8 · 6x + 3 = 15, x = 2 · 6x + 3 = 9, x = 1 · 6x + 7 = 73, x = 11 · 4x + 1 = 17, x = 4 · 4x + 4 = 52, x = 12

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 Subzero Cipher — set in The Vanguard Spy Academy Mainframe Vault
Format
Interactive online & printable worksheet with answer key
Solution
One unique, verified culprit among 21 suspects

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