🌊 MermaidsGrade 6Reading: grades 3-4Place valueMultiplicationMulti-step word problemsWord problemsDivision
The Mystery of the Golden Pearl
The legendary Golden Pearl of Coral Cove has been stolen! The Royal Reef Keeper is devastated and needs your help. The coral crook left a trail of clues across the glowing sea floor. Swim fast and use your math skills to help the Coral Patrol track down the thief!
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 | Main Magic | Seabed Skill | Swimming Style | Hair Type | Fear |
|---|---|---|---|---|---|
| Nerida | wave blast | jellyfish sting | right-finned | starfish orange | bright light |
| Triton | coral shield | clam dig | left-finned | starfish orange | tickle feather |
| Sandy | kelp tangle | clam dig | right-finned | seaweed green | loud whistle |
| Coral | kelp tangle | sonic song | right-finned | starfish orange | bright light |
| Brooke | kelp tangle | sonic song | left-finned | starfish orange | tickle feather |
| Delphine | coral shield | jellyfish sting | right-finned | seaweed green | tickle feather |
| Marina | coral shield | starfish climb | left-finned | starfish orange | loud whistle |
| Sirena | wave blast | clam dig | left-finned | starfish orange | tickle feather |
| Hali | kelp tangle | sonic song | left-finned | seaweed green | tickle feather |
| Shelly | kelp tangle | clam dig | right-finned | seaweed green | bright light |
| Kai | bubble trap | jellyfish sting | left-finned | starfish orange | tickle feather |
| Tallulah | kelp tangle | jellyfish sting | left-finned | seaweed green | loud whistle |
| Morgan | kelp tangle | starfish climb | left-finned | anemone pink | loud whistle |
| Ursula | bubble trap | jellyfish sting | right-finned | seaweed green | bright light |
| Pearl | bubble trap | sonic song | right-finned | starfish orange | tickle feather |
| Wave | whirlpool spin | jellyfish sting | right-finned | starfish orange | loud whistle |
| Pacifica | coral shield | clam dig | left-finned | seaweed green | tickle feather |
| Caspian | coral shield | sonic song | left-finned | starfish orange | tickle feather |
| Coralia | whirlpool spin | sonic song | right-finned | anemone pink | bright light |
| Aqua | coral shield | fish speak | left-finned | anemone pink | bright light |
| Finley | bubble trap | clam dig | left-finned | anemone pink | bright light |
Clue 1
Place value
A glowing starfish points to a secret map on the wall. The map uses large numbers to show the path of the thief. Look at the place value of the digits to unlock the first clue.
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
1000
70
7000
30
500
60
60
300
5000
60
7000
50
600
60
T
1000
70
2000
800
7000
3000
7000
40
40
100
20
4000
50
70
50
T
1000
4000
600
10
What is the value of the 1 in 91,700?T
What is the value of the 7 in 11,976?H
What is the value of the 5 in 37,350?S
What is the value of the 3 in 255,368?K
What is the value of the 8 in 396,873?V
What is the value of the 6 in 804,692?N
What is the value of the 5 in 695,449?D
What is the value of the 1 in 68,919?G
What is the value of the 3 in 53,405?J
What is the value of the 2 in 535,923?F
What is the value of the 5 in 976,543?R
What is the value of the 6 in 713,869?O
What is the value of the 4 in 83,941?L
What is the value of the 7 in 57,281?E
What is the value of the 2 in 912,761?A
What is the value of the 4 in 64,323?I
What is the value of the 3 in 69,438?C
What is the value of the 1 in 664,149?Y
0/18 letters found
Clue 2
Multiplication facts (1-12)
The thief left tail prints in neat rows on the sandy floor. Count the rows and multiply them to see where they swam next. Solving this will reveal the thief's swimming style.
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
121
12
54
4
80
18
18
56
64
24
50
99
64
24
50
T
121
12
T
121
12
54
3
54
60
T
121
60
50
36
18
36
3
110
11 × 11 =T
8 × 7 =K
9 × 11 =M
3 × 8 =W
10 × 8 =R
11 × 10 =Y
5 × 12 =F
4 × 1 =C
6 × 2 =H
3 × 6 =O
1 × 3 =L
10 × 5 =I
8 × 8 =S
4 × 9 =N
9 × 6 =E
0/15 letters found
Clue 3
Multi-step word problems
A school of helpful sea turtles wants to help us search. They need to pack bags of kelp snacks for their long swim. Help them count the snacks in multiple steps to find the thief's fear.
Solve each problem to learn its letter, then write the letters in the boxes to fill in the missing word.
Someonescaredthevillainoffwith .
T
22
76
62
66
13
12
90
12
A
T
22
H
12
R
Coralia earned 7 kelp cakes in each of 3 rounds, plus 11 bonus kelp cakes. Then 10 kelp cakes were lost. How many kelp cakes are left?T
There were 204 clamshells in all. 1 Guppy Scouts used 24 clamshells each. The other 2 Guppy Scouts shared the rest equally. How many clamshells did each of the other Guppy Scouts get?F
Coralia collected 168 sea pearls in the morning and 204 sea pearls in the afternoon, then split them equally among 6 Guppy Scouts. How many sea pearls did each get?C
There were 123 sea glass in all. 3 Guppy Scouts used 17 sea glass each. The other 6 Guppy Scouts shared the rest equally. How many sea glass did each of the other Guppy Scouts get?E
Coralia collected 124 kelp cakes in the morning and 74 kelp cakes in the afternoon, then split them equally among 3 Guppy Scouts. How many kelp cakes did each get?K
Coralia filled 2 boxes with 3 sea pearls each, then found 7 more sea pearls. How many sea pearls are there in all?L
Coralia collected 197 sea glass in the morning and 183 sea glass in the afternoon, then split them equally among 5 Guppy Scouts. How many sea glass did each get?I
0/7 letters found
Clue 4
Word problems
We found some dropped treasure boxes near the coral reef. If we solve the word problem about these lost items, we can find a clue about the thief's hair color.
Solve each problem to learn its letter, then write the letters in the boxes to fill in the missing word.
Astrandof hairturnedupatthescene.
S
74
117
36
52
93
17
S
74
9
O
52
36
N
G
E
Coralia found 49 starfish yesterday and 25 more today. How many starfish in all?S
There were 29 sea pearls. 20 were used up. How many sea pearls are left?H
There were 68 sea pearls. 16 were used up. How many sea pearls are left?R
There were 57 sea glass. 40 were used up. How many sea glass are left?I
Coralia found 38 clamshells yesterday and 79 more today. How many clamshells in all?T
Coralia found 81 sea glass yesterday and 12 more today. How many sea glass in all?F
Coralia lined up 6 rows of 6 kelp cakes. How many kelp cakes in all?A
0/7 letters found
Clue 5
Division facts (1-12) — the last clue
The Coral Patrol needs to share their search gear evenly among the team. Split the rescue rings into equal groups to unlock the final clue.
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
24 ÷ 12 = ?
84 ÷ 7 = ?
64 ÷ 8 = ?
32 ÷ 8 = ?
36 ÷ 6 = ?
100 ÷ 10 = ?
108 ÷ 12 = ?
63 ÷ 9 = ?
36 ÷ 12 = ?
30 ÷ 6 = ?
22 ÷ 2 = ?
Step 2 — cross out the sentence with each answer
1.The villain tangles paths with kelp, then sings a loud sonic song.
2.The villain blocks doors with coral, then sings a loud sonic song.
3.The villain blasts guards with waves, then sings a loud sonic song.
4.The villain blasts guards with waves, then climbs walls with starfish.
5.The villain spins a giant whirlpool, then climbs walls with starfish.
6.The villain blocks doors with coral, then calls tiny fish for help.
7.The villain blasts guards with waves, then calls tiny fish for help.
8.The villain blocks doors with coral, then digs through sand with clams.
9.The villain tangles paths with kelp, then calls tiny fish for help.
10.The villain spins a giant whirlpool, then sings a loud sonic song.
11.The villain tangles paths with kelp, then stings locks with jellyfish.
12.The villain blasts guards with waves, then digs through sand with clams.
Solve it
Name the culprit
Choose the one suspect left standing.
Answer Key — The Mystery of the Golden Pearl
Culprit: Brooke (kelp tangle · sonic song · left-finned · starfish orange · tickle feather)
- Clue 1 (Place value): "THE CROOK DOES NOT HAVE JELLYFISH STING"What is the value of the 1 in 91,700? = 1000 (T) · What is the value of the 7 in 11,976? = 70 (H) · What is the value of the 5 in 37,350? = 50 (S) · What is the value of the 3 in 255,368? = 300 (K) · What is the value of the 8 in 396,873? = 800 (V) · What is the value of the 6 in 804,692? = 600 (N) · What is the value of the 5 in 695,449? = 5000 (D) · What is the value of the 1 in 68,919? = 10 (G) · What is the value of the 3 in 53,405? = 3000 (J) · What is the value of the 2 in 535,923? = 20 (F) · What is the value of the 5 in 976,543? = 500 (R) · What is the value of the 6 in 713,869? = 60 (O) · What is the value of the 4 in 83,941? = 40 (L) · What is the value of the 7 in 57,281? = 7000 (E) · What is the value of the 2 in 912,761? = 2000 (A) · What is the value of the 4 in 64,323? = 4000 (I) · What is the value of the 3 in 69,438? = 30 (C) · What is the value of the 1 in 664,149? = 100 (Y)
- Clue 2 (Multiplication facts (1-12)): "THE CROOK SWIMS WITH THE LEFT FIN ONLY"11 × 11 = 121 (T) · 8 × 7 = 56 (K) · 9 × 11 = 99 (M) · 3 × 8 = 24 (W) · 10 × 8 = 80 (R) · 11 × 10 = 110 (Y) · 5 × 12 = 60 (F) · 4 × 1 = 4 (C) · 6 × 2 = 12 (H) · 3 × 6 = 18 (O) · 1 × 3 = 3 (L) · 10 × 5 = 50 (I) · 8 × 8 = 64 (S) · 4 × 9 = 36 (N) · 9 × 6 = 54 (E)
- Clue 3 (Multi-step word problems): "TICKLE FEATHER"Coralia earned 7 kelp cakes in each of 3 rounds, plus 11 bonus kelp cakes. Then 10 kelp cakes were lost. How many kelp cakes are left? = 22 (T) · There were 204 clamshells in all. 1 Guppy Scouts used 24 clamshells each. The other 2 Guppy Scouts shared the rest equally. How many clamshells did each of the other Guppy Scouts get? = 90 (F) · Coralia collected 168 sea pearls in the morning and 204 sea pearls in the afternoon, then split them equally among 6 Guppy Scouts. How many sea pearls did each get? = 62 (C) · There were 123 sea glass in all. 3 Guppy Scouts used 17 sea glass each. The other 6 Guppy Scouts shared the rest equally. How many sea glass did each of the other Guppy Scouts get? = 12 (E) · Coralia collected 124 kelp cakes in the morning and 74 kelp cakes in the afternoon, then split them equally among 3 Guppy Scouts. How many kelp cakes did each get? = 66 (K) · Coralia filled 2 boxes with 3 sea pearls each, then found 7 more sea pearls. How many sea pearls are there in all? = 13 (L) · Coralia collected 197 sea glass in the morning and 183 sea glass in the afternoon, then split them equally among 5 Guppy Scouts. How many sea glass did each get? = 76 (I)
- Clue 4 (Word problems): "STARFISH ORANGE"Coralia found 49 starfish yesterday and 25 more today. How many starfish in all? = 74 (S) · There were 29 sea pearls. 20 were used up. How many sea pearls are left? = 9 (H) · There were 68 sea pearls. 16 were used up. How many sea pearls are left? = 52 (R) · There were 57 sea glass. 40 were used up. How many sea glass are left? = 17 (I) · Coralia found 38 clamshells yesterday and 79 more today. How many clamshells in all? = 117 (T) · Coralia found 81 sea glass yesterday and 12 more today. How many sea glass in all? = 93 (F) · Coralia lined up 6 rows of 6 kelp cakes. How many kelp cakes in all? = 36 (A)
- Clue 5 (Division facts (1-12)): surviving statement (box 1) → Brooke24 ÷ 12 = 2 · 84 ÷ 7 = 12 · 64 ÷ 8 = 8 · 32 ÷ 8 = 4 · 36 ÷ 6 = 6 · 100 ÷ 10 = 10 · 108 ÷ 12 = 9 · 63 ÷ 9 = 7 · 36 ÷ 12 = 3 · 30 ÷ 6 = 5 · 22 ÷ 2 = 11
About this mystery
- Grade level
- Grade 6 math
- Math topics
- Place value, Multiplication, Multi-step word problems, Word problems, Division
- Reading level
- grades 3-4
- Theme
- The Mystery of the Golden Pearl — set in Coral Cove
- Format
- Interactive online & printable worksheet with answer key
- Solution
- One unique, verified culprit among 21 suspects