🔎 BooksGrade 7Reading: grades 5-6Fractions of a numberMultiplicationMulti-step word problemsIntegers
The Mystery of the Great Archive
Someone mixed up all the rare manuscripts in the Great Archive and blotted out the author signatures! Use your detective skills and solve the clues to catch the Ink Bandit before the literary festival begins.
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 | Literary Genre | Bookmark Style | Writing Hand | Ink Stain Color | Literary Foil |
|---|---|---|---|---|---|
| Harry Potter | Historical Saga | Dragon Tassel | Left Handed | Crimson Red | Loud Noise |
| Elizabeth Bennet | Poetry Verse | Neon Sticker | Left Handed | Midnight Blue | Harsh Sunlight |
| Nancy Drew | Poetry Verse | Leather Strap | Left Handed | Raven Black | Harsh Sunlight |
| Mary Poppins | Fantasy Lore | Neon Sticker | Right Handed | Crimson Red | Loud Noise |
| Hermione Granger | Sci-Fi Epic | Dragon Tassel | Right Handed | Crimson Red | Harsh Sunlight |
| Hercule Poirot | Sci-Fi Epic | Leather Strap | Left Handed | Midnight Blue | Harsh Sunlight |
| Katniss Everdeen | Mystery Fiction | Silver Ribbon | Left Handed | Midnight Blue | Harsh Sunlight |
| Tom Sawyer | Historical Saga | Neon Sticker | Right Handed | Crimson Red | Loud Noise |
| Augustus Bucket | Poetry Verse | Brass Clip | Left Handed | Raven Black | Fresh Glue |
| Percy Jackson | Historical Saga | Dragon Tassel | Left Handed | Crimson Red | Harsh Sunlight |
| Jay Gatsby | Mystery Fiction | Brass Clip | Right Handed | Raven Black | Loud Noise |
| Phileas Fogg | Sci-Fi Epic | Silver Ribbon | Left Handed | Raven Black | Harsh Sunlight |
| Captain Nemo | Poetry Verse | Leather Strap | Left Handed | Midnight Blue | Fresh Glue |
| Dorothy Gale | Poetry Verse | Dragon Tassel | Left Handed | Raven Black | Loud Noise |
| Bilbo Baggins | Poetry Verse | Dragon Tassel | Right Handed | Raven Black | Loud Noise |
| Atticus Finch | Fantasy Lore | Brass Clip | Right Handed | Midnight Blue | Fresh Glue |
| Holden Caulfield | Fantasy Lore | Brass Clip | Left Handed | Raven Black | Harsh Sunlight |
| Jo March | Poetry Verse | Silver Ribbon | Left Handed | Raven Black | Harsh Sunlight |
| Meg Murry | Sci-Fi Epic | Brass Clip | Left Handed | Raven Black | Loud Noise |
| Ebenezer Scrooge | Poetry Verse | Dragon Tassel | Left Handed | Raven Black | Harsh Sunlight |
| Huckleberry Finn | Mystery Fiction | Leather Strap | Right Handed | Raven Black | Harsh Sunlight |
Clue 1
Fractions of a number
The library assistant calculated that only a fraction of the damaged mystery manuscripts could be restored today.
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
52
31
21
24
20
20
35
24
47
38
37
31
60
47
37
T
50
2
60
31
35
38
58
35
23
37
47
T
50
35
60
60
31
20
3/6 of 100 =T
2/5 of 50 =L
1/6 of 186 =E
2/5 of 145 =R
3/10 of 80 =I
4/8 of 74 =O
2/8 of 140 =A
1/10 of 20 =U
2/8 of 84 =V
2/4 of 94 =N
3/6 of 76 =D
5/6 of 72 =S
3/6 of 46 =G
2/5 of 130 =H
0/14 letters found
Clue 2
Multiplication facts (1-12)
The head investigator organized the recovered book stacks into equal rows to compute the total count.
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
60
8
81
6
90
6
25
81
121
T
60
24
54
6
24
12
84
T
60
84
7
42
24
84
T
60
8
T
60
8
81
84
12
32
81
48
T
60
8
54
7
14
12 × 5 =T
9 × 9 =E
9 × 10 =U
4 × 3 =R
12 × 7 =I
6 × 9 =A
2 × 12 =W
5 × 5 =P
1 × 7 =N
2 × 7 =D
6 × 1 =S
11 × 11 =C
7 × 6 =G
1 × 8 =H
4 × 8 =L
4 × 12 =F
0/16 letters found
Clue 3
Multi-step word problems
To track down the culprit, the detective calculated the total budget spent on replacement covers minus the discount.
Solve each problem to learn its letter, then write the letters in the boxes to fill in the missing word.
Someonescaredthevillainoffwith .
H
84
6
70
28
H
84
28
7
47
67
I
G
H
84
T
Archivist filled 7 boxes with 8 leather journals each, then found 28 more leather journals. How many leather journals are there in all?H
There were 297 leather journals in all. 29 leather journals were set aside. The rest were shared equally among 4 the Reading Guild. How many leather journals did each get?L
Archivist earned 6 magnifying glasses in each of 5 rounds, plus 23 bonus magnifying glasses. Then 6 magnifying glasses were lost. How many magnifying glasses are left?N
Archivist earned 3 quill pens in each of 5 rounds, plus 1 bonus quill pens. Then 9 quill pens were lost. How many quill pens are left?U
There were 170 quill pens in all. 30 quill pens were set aside. The rest were shared equally among 5 the Reading Guild. How many quill pens did each get?S
Archivist collected 27 bookmark tassels in the morning and 3 bookmark tassels in the afternoon, then split them equally among 5 the Reading Guild. How many bookmark tassels did each get?A
Archivist collected 202 bookmark tassels in the morning and 78 bookmark tassels in the afternoon, then split them equally among 4 the Reading Guild. How many bookmark tassels did each get?R
0/7 letters found
Clue 4
Integers
The archival thermometer tracked temperature changes in the vault above and below zero degrees.
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
6
14
13
8
A
6
20
24
28
4
8
A
6
27
16
20
15
10
A
6
3
9
18
A
6
26
8
17
A
6
14
4
28
30
20
24
(-12) + 18 =A
(-11) + 19 =R
6 - (-4) =L
(-7) + 21 =S
(-1) + 21 =N
(-4) + 13 =K
(-6) + 19 =T
(-12) + 27 =B
(-15) + 31 =E
12 - (-14) =I
18 - (-12) =U
13 - (-15) =O
14 - (-4) =H
15 - (-12) =V
(-15) + 18 =C
1 - (-3) =F
(-5) + 22 =W
15 - (-9) =D
0/18 letters found
Clue 5
Fractions of a number — the last clue
A fraction of the remaining reference scrolls contained hidden marginal notes from the suspect.
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
1/3 of 9 = ?
1/3 of 24 = ?
1/8 of 40 = ?
2/8 of 16 = ?
1/5 of 35 = ?
1/3 of 18 = ?
1/4 of 4 = ?
3/5 of 15 = ?
1/6 of 60 = ?
6/8 of 16 = ?
1/10 of 110 = ?
Step 2 — cross out the sentence with each answer
1.The villain rewrote the mystery finale, then decorated drafts with a dragon tassel.
2.The villain scrambled the rhyming stanzas, then marked pages with a silver ribbon.
3.The villain erased the sci-fi star map, then marked pages with a silver ribbon.
4.The villain rewrote the mystery finale, then tagged pages with a neon sticker.
5.The villain scrambled the fantasy spells, then clipped notes with a brass clip.
6.The villain altered the historical dates, then marked pages with a silver ribbon.
7.The villain altered the historical dates, then bound chapters with a leather strap.
8.The villain scrambled the rhyming stanzas, then bound chapters with a leather strap.
9.The villain erased the sci-fi star map, then bound chapters with a leather strap.
10.The villain erased the sci-fi star map, then decorated drafts with a dragon tassel.
11.The villain scrambled the rhyming stanzas, then clipped notes with a brass clip.
12.The villain erased the sci-fi star map, then clipped notes with a brass clip.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of the Great Archive
Culprit: Jo March (Poetry Verse · Silver Ribbon · Left Handed · Raven Black · Harsh Sunlight)
- Clue 1 (Fractions of a number): "THE VILLAIN DOES NOT USE A DRAGON TASSEL"3/6 of 100 = 50 (T) · 2/5 of 50 = 20 (L) · 1/6 of 186 = 31 (E) · 2/5 of 145 = 58 (R) · 3/10 of 80 = 24 (I) · 4/8 of 74 = 37 (O) · 2/8 of 140 = 35 (A) · 1/10 of 20 = 2 (U) · 2/8 of 84 = 21 (V) · 2/4 of 94 = 47 (N) · 3/6 of 76 = 38 (D) · 5/6 of 72 = 60 (S) · 3/6 of 46 = 23 (G) · 2/5 of 130 = 52 (H)
- Clue 2 (Multiplication facts (1-12)): "THE SUSPECT WAS WRITING WITH THEIR LEFT HAND"12 × 5 = 60 (T) · 9 × 9 = 81 (E) · 9 × 10 = 90 (U) · 4 × 3 = 12 (R) · 12 × 7 = 84 (I) · 6 × 9 = 54 (A) · 2 × 12 = 24 (W) · 5 × 5 = 25 (P) · 1 × 7 = 7 (N) · 2 × 7 = 14 (D) · 6 × 1 = 6 (S) · 11 × 11 = 121 (C) · 7 × 6 = 42 (G) · 1 × 8 = 8 (H) · 4 × 8 = 32 (L) · 4 × 12 = 48 (F)
- Clue 3 (Multi-step word problems): "HARSH SUNLIGHT"Archivist filled 7 boxes with 8 leather journals each, then found 28 more leather journals. How many leather journals are there in all? = 84 (H) · There were 297 leather journals in all. 29 leather journals were set aside. The rest were shared equally among 4 the Reading Guild. How many leather journals did each get? = 67 (L) · Archivist earned 6 magnifying glasses in each of 5 rounds, plus 23 bonus magnifying glasses. Then 6 magnifying glasses were lost. How many magnifying glasses are left? = 47 (N) · Archivist earned 3 quill pens in each of 5 rounds, plus 1 bonus quill pens. Then 9 quill pens were lost. How many quill pens are left? = 7 (U) · There were 170 quill pens in all. 30 quill pens were set aside. The rest were shared equally among 5 the Reading Guild. How many quill pens did each get? = 28 (S) · Archivist collected 27 bookmark tassels in the morning and 3 bookmark tassels in the afternoon, then split them equally among 5 the Reading Guild. How many bookmark tassels did each get? = 6 (A) · Archivist collected 202 bookmark tassels in the morning and 78 bookmark tassels in the afternoon, then split them equally among 4 the Reading Guild. How many bookmark tassels did each get? = 70 (R)
- Clue 4 (Integers): "A STRAND OF RAVEN BLACK HAIR WAS FOUND"(-12) + 18 = 6 (A) · (-11) + 19 = 8 (R) · 6 - (-4) = 10 (L) · (-7) + 21 = 14 (S) · (-1) + 21 = 20 (N) · (-4) + 13 = 9 (K) · (-6) + 19 = 13 (T) · (-12) + 27 = 15 (B) · (-15) + 31 = 16 (E) · 12 - (-14) = 26 (I) · 18 - (-12) = 30 (U) · 13 - (-15) = 28 (O) · 14 - (-4) = 18 (H) · 15 - (-12) = 27 (V) · (-15) + 18 = 3 (C) · 1 - (-3) = 4 (F) · (-5) + 22 = 17 (W) · 15 - (-9) = 24 (D)
- Clue 5 (Fractions of a number): surviving statement (box 2) → Jo March1/3 of 9 = 3 · 1/3 of 24 = 8 · 1/8 of 40 = 5 · 2/8 of 16 = 4 · 1/5 of 35 = 7 · 1/3 of 18 = 6 · 1/4 of 4 = 1 · 3/5 of 15 = 9 · 1/6 of 60 = 10 · 6/8 of 16 = 12 · 1/10 of 110 = 11
About this mystery
- Grade level
- Grade 7 math
- Math topics
- Fractions of a number, Multiplication, Multi-step word problems, Integers
- Reading level
- grades 5-6
- Theme
- The Mystery of the Great Archive — set in The Alexandria Library School
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects