🔎 Real empires geography and hGrade 4Reading: grades 5-6Place valueRoundingAdditionSubtractionDivision
The Imperial Map Mystery
An ancient, priceless map showing the secret borders of the lost empires has been stolen from the Imperial Archive. The Chief Archivist needs your help to track down the historical thief before they sell the map to the highest bidder!
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 | Empire Specialty | Secret Resource | Writing Hand | Hair Style | Known Weakness |
|---|---|---|---|---|---|
| Genghis | Mongol horse archery | Bronze compasses | Left handed writing | Braided hair | Allergic to horse fur |
| Charlemagne | Egyptian stone masonry | Spices and gold | Right handed writing | Short cropped hair | Afraid of deep water |
| Montezuma | Egyptian stone masonry | Spices and gold | Left handed writing | Short cropped hair | Allergic to horse fur |
| Cyrus | Aztec canal systems | Spices and gold | Right handed writing | Short cropped hair | Afraid of deep water |
| Leonidas | Mongol horse archery | Spices and gold | Left handed writing | Braided hair | Allergic to horse fur |
| Mansa Musa | Aztec canal systems | Spices and gold | Right handed writing | Short cropped hair | Cannot stand the cold |
| Alfred | Mongol horse archery | Spices and gold | Left handed writing | Braided hair | Cannot stand the cold |
| Kublai | Viking shipbuilding | Bronze compasses | Left handed writing | Short cropped hair | Allergic to horse fur |
| Isabella | Roman legion tactics | Silk road maps | Left handed writing | Short cropped hair | Allergic to horse fur |
| Suleiman | Aztec canal systems | Papyrus scrolls | Left handed writing | Short cropped hair | Allergic to horse fur |
| Nefertiti | Aztec canal systems | Silk road maps | Right handed writing | Braided hair | Allergic to horse fur |
| Theodora | Viking shipbuilding | Papyrus scrolls | Left handed writing | Short cropped hair | Afraid of deep water |
| Julius | Mongol horse archery | Astrolabe charts | Right handed writing | Short cropped hair | Allergic to horse fur |
| Hammurabi | Egyptian stone masonry | Spices and gold | Left handed writing | Wavy shoulder hair | Afraid of deep water |
| Atahualpa | Roman legion tactics | Spices and gold | Left handed writing | Braided hair | Afraid of deep water |
| Pachacuti | Roman legion tactics | Bronze compasses | Left handed writing | Short cropped hair | Afraid of deep water |
| Alexander | Viking shipbuilding | Astrolabe charts | Left handed writing | Short cropped hair | Allergic to horse fur |
| Darius | Aztec canal systems | Bronze compasses | Left handed writing | Braided hair | Allergic to horse fur |
| Justinian | Egyptian stone masonry | Papyrus scrolls | Right handed writing | Short cropped hair | Allergic to horse fur |
| Ashoka | Roman legion tactics | Spices and gold | Right handed writing | Wavy shoulder hair | Afraid of deep water |
| Zenobia | Mongol horse archery | Papyrus scrolls | Left handed writing | Short cropped hair | Cannot stand the cold |
Clue 1
Place value
We found a secret code book used by the thief. The digit in the hundreds place reveals the hidden locker.
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
400
500
90
T
400
500
10
90
50
4000
6000
90
5000
3000
6000
T
400
20
5000
90
5000
300
10
800
90
5000
700
3000
4000
7000
6000
8000
4000
What is the value of the 4 in 491?T
What is the value of the 5 in 573?H
What is the value of the 2 in 4,120?U
What is the value of the 7 in 780?A
What is the value of the 1 in 2,415?I
What is the value of the 4 in 4,380?D
What is the value of the 8 in 8,673?L
What is the value of the 8 in 896?C
What is the value of the 7 in 17,039?G
What is the value of the 9 in 192?E
What is the value of the 6 in 6,729?O
What is the value of the 3 in 83,655?N
What is the value of the 5 in 5,643?S
What is the value of the 5 in 759?F
What is the value of the 3 in 7,322?P
0/15 letters found
Clue 2
Rounding
A scout reported seeing the suspect running away. He had to round the distance to the nearest ten miles to map it.
Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.
L
20
50
70
2000
3700
430
90
30
50
30
110
90
3000
700
900
5000
30
170
50
700
7000
50
9000
50
70
2300
5000
90
30
Round 23 to the nearest tenL
Round 430 to the nearest tenA
Round 6,729 to the nearest thousandW
Round 915 to the nearest hundredM
Round 31 to the nearest tenD
Round 686 to the nearest hundredS
Round 2,296 to the nearest hundredO
Round 174 to the nearest tenG
Round 2,630 to the nearest thousandK
Round 1,557 to the nearest thousandT
Round 51 to the nearest tenE
Round 8,936 to the nearest thousandR
Round 108 to the nearest tenI
Round 71 to the nearest tenF
Round 3,688 to the nearest hundredH
Round 90 to the nearest tenN
Round 4,701 to the nearest thousandU
0/17 letters found
Clue 3
Addition
To find the suspect's supply route, we must add up all the trading outposts along the Silk Road.
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
5684
6986
9747
9747
3055
5644
6986
2496
S
5684
3597
2822
6986
2742
S
5684
3969
9747
8398
2771
2742
6986
9747
8398
2771
2966
3969
9747
S
5684
2966
8398
7293
3452
9747
S
5684
3848 + 1836 =S
4630 + 3768 =A
1858 + 1108 =T
2195 + 1257 =L
1033 + 1709 =D
1122 + 1374 =G
6550 + 3197 =E
2360 + 1237 =O
1013 + 2042 =Z
3908 + 1736 =I
1747 + 2222 =H
2110 + 4876 =N
1406 + 1365 =R
3027 + 4266 =B
891 + 1931 =U
0/15 letters found
Clue 4
Subtraction
We can calculate how much gold the thief stole by subtracting the remaining coins from the vault total.
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
8748
4572
8020
6840
5386
6336
6840
8020
6626
6626
5769
3686
4572
1263
8231
6840
7513
1263
S
8748
8020
1017
5386
4572
5769
6336
4572
1263
8231
6840
13161 - 4413 =S
2897 - 1880 =N
12562 - 4542 =O
8115 - 602 =W
8267 - 36 =I
8543 - 1917 =P
6954 - 2382 =H
9308 - 3922 =T
5232 - 1546 =D
2690 - 1427 =A
9931 - 4162 =E
9840 - 3000 =R
7582 - 1246 =C
0/13 letters found
Clue 5
Division facts (1-12) — the last clue
The chief investigator wants to divide the search area equally among our fast horse riders.
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
16 ÷ 2 = ?
4 ÷ 2 = ?
110 ÷ 11 = ?
77 ÷ 11 = ?
88 ÷ 8 = ?
108 ÷ 9 = ?
4 ÷ 4 = ?
27 ÷ 9 = ?
18 ÷ 3 = ?
90 ÷ 10 = ?
30 ÷ 6 = ?
Step 2 — cross out the sentence with each answer
1.The villain builds the lake canals, then consults the astrolabe charts.
2.The villain sails the longships, then consults the astrolabe charts.
3.The villain carves the limestone, then polishes the bronze compasses.
4.The villain sails the longships, then polishes the bronze compasses.
5.The villain sails the longships, then steals silk road maps.
6.The villain carves the limestone, then hoards the spices and gold.
7.The villain sails the longships, then hides the papyrus scrolls.
8.The villain builds the lake canals, then hides the papyrus scrolls.
9.The villain marches with the legions, then hides the papyrus scrolls.
10.The villain marches with the legions, then steals silk road maps.
11.The villain marches with the legions, then polishes the bronze compasses.
12.The villain marches with the legions, then hoards the spices and gold.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Imperial Map Mystery
Culprit: Kublai (Viking shipbuilding · Bronze compasses · Left handed writing · Short cropped hair · Allergic to horse fur)
- Clue 1 (Place value): "THE THIEF DOES NOT USE SPICES AND GOLD"What is the value of the 4 in 491? = 400 (T) · What is the value of the 5 in 573? = 500 (H) · What is the value of the 2 in 4,120? = 20 (U) · What is the value of the 7 in 780? = 700 (A) · What is the value of the 1 in 2,415? = 10 (I) · What is the value of the 4 in 4,380? = 4000 (D) · What is the value of the 8 in 8,673? = 8000 (L) · What is the value of the 8 in 896? = 800 (C) · What is the value of the 7 in 17,039? = 7000 (G) · What is the value of the 9 in 192? = 90 (E) · What is the value of the 6 in 6,729? = 6000 (O) · What is the value of the 3 in 83,655? = 3000 (N) · What is the value of the 5 in 5,643? = 5000 (S) · What is the value of the 5 in 759? = 50 (F) · What is the value of the 3 in 7,322? = 300 (P)
- Clue 2 (Rounding): "LEFT HANDED INK SMUDGES WERE FOUND"Round 23 to the nearest ten = 20 (L) · Round 430 to the nearest ten = 430 (A) · Round 6,729 to the nearest thousand = 7000 (W) · Round 915 to the nearest hundred = 900 (M) · Round 31 to the nearest ten = 30 (D) · Round 686 to the nearest hundred = 700 (S) · Round 2,296 to the nearest hundred = 2300 (O) · Round 174 to the nearest ten = 170 (G) · Round 2,630 to the nearest thousand = 3000 (K) · Round 1,557 to the nearest thousand = 2000 (T) · Round 51 to the nearest ten = 50 (E) · Round 8,936 to the nearest thousand = 9000 (R) · Round 108 to the nearest ten = 110 (I) · Round 71 to the nearest ten = 70 (F) · Round 3,688 to the nearest hundred = 3700 (H) · Round 90 to the nearest ten = 90 (N) · Round 4,701 to the nearest thousand = 5000 (U)
- Clue 3 (Addition): "SNEEZING SOUNDS HEARD NEAR THE STABLES"3848 + 1836 = 5684 (S) · 4630 + 3768 = 8398 (A) · 1858 + 1108 = 2966 (T) · 2195 + 1257 = 3452 (L) · 1033 + 1709 = 2742 (D) · 1122 + 1374 = 2496 (G) · 6550 + 3197 = 9747 (E) · 2360 + 1237 = 3597 (O) · 1013 + 2042 = 3055 (Z) · 3908 + 1736 = 5644 (I) · 1747 + 2222 = 3969 (H) · 2110 + 4876 = 6986 (N) · 1406 + 1365 = 2771 (R) · 3027 + 4266 = 7293 (B) · 891 + 1931 = 2822 (U)
- Clue 4 (Subtraction): "SHORT CROPPED HAIR WAS ON THE CHAIR"13161 - 4413 = 8748 (S) · 2897 - 1880 = 1017 (N) · 12562 - 4542 = 8020 (O) · 8115 - 602 = 7513 (W) · 8267 - 36 = 8231 (I) · 8543 - 1917 = 6626 (P) · 6954 - 2382 = 4572 (H) · 9308 - 3922 = 5386 (T) · 5232 - 1546 = 3686 (D) · 2690 - 1427 = 1263 (A) · 9931 - 4162 = 5769 (E) · 9840 - 3000 = 6840 (R) · 7582 - 1246 = 6336 (C)
- Clue 5 (Division facts (1-12)): surviving statement (box 4) → Kublai16 ÷ 2 = 8 · 4 ÷ 2 = 2 · 110 ÷ 11 = 10 · 77 ÷ 11 = 7 · 88 ÷ 8 = 11 · 108 ÷ 9 = 12 · 4 ÷ 4 = 1 · 27 ÷ 9 = 3 · 18 ÷ 3 = 6 · 90 ÷ 10 = 9 · 30 ÷ 6 = 5
About this mystery
- Grade level
- Grade 4 math
- Math topics
- Place value, Rounding, Addition, Subtraction, Division
- Reading level
- grades 5-6
- Theme
- The Imperial Map Mystery — set in The Great Library of the Ancient World
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects