🏴‍☠️ PiratesGrade 4Reading: grades 3-4RoundingWord problemsAdditionSubtractionDivision

The Mystery of Barnacle Bay

Someone snuck onto the flagship ship and stole the golden compass! Work through the clues to discover which sneaky pirate pulled off the heist.

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 Weapon	Sailing Gear	Stance	Hat Style	Fear
Olivier Levasseur	Cannonball	Rope Ladder	Right Handed	Black Bandana	Parrot Squawks
Edward Low	Flintlock	Iron Anchor	Left Handed	Red Tricorn	Bright Searchlights
Edward England	Grappling Hook	Map Scroll	Right Handed	Red Tricorn	Tickling Seaweed
George Lowther	Cutlass	Spyglass	Left Handed	Black Bandana	Tickling Seaweed
Blackbeard	Flintlock	Spyglass	Right Handed	Black Bandana	Parrot Squawks
William Kidd	Grappling Hook	Rope Ladder	Right Handed	Black Bandana	Parrot Squawks
Calico Jack	Grappling Hook	Brass Compass	Right Handed	Black Bandana	Bright Searchlights
Stede Bonnet	Grappling Hook	Iron Anchor	Right Handed	Black Bandana	Tickling Seaweed
Samuel Bellamy	Cannonball	Rope Ladder	Left Handed	Feathered Cap	Bright Searchlights
Thomas Tew	Cutlass	Brass Compass	Right Handed	Black Bandana	Bright Searchlights
Christopher Condent	Flintlock	Map Scroll	Left Handed	Red Tricorn	Bright Searchlights
Grace O Malley	Cannonball	Brass Compass	Right Handed	Black Bandana	Parrot Squawks
Bartholomew Roberts	Flintlock	Brass Compass	Left Handed	Black Bandana	Bright Searchlights
Charles Vane	Cutlass	Map Scroll	Right Handed	Feathered Cap	Parrot Squawks
Mary Read	Wooden Staff	Spyglass	Right Handed	Black Bandana	Tickling Seaweed
Charlotte de Berry	Flintlock	Iron Anchor	Right Handed	Feathered Cap	Parrot Squawks
Howell Davis	Cannonball	Spyglass	Left Handed	Black Bandana	Parrot Squawks
John Evans	Grappling Hook	Map Scroll	Right Handed	Black Bandana	Parrot Squawks
Woodes Rogers	Cannonball	Brass Compass	Right Handed	Feathered Cap	Parrot Squawks
Richard Worley	Cutlass	Brass Compass	Left Handed	Red Tricorn	Parrot Squawks
Salty Sam	Grappling Hook	Map Scroll	Left Handed	Feathered Cap	Parrot Squawks

Clue 1

Rounding

You inspect the cargo ledger to narrow down suspect clues.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

130

900

700

3000

1100

230

3000

7000

430

900

500

430

130

170

500

900

230

500

5000

370

430

1100

Round 127 to the nearest tenT

Round 51 to the nearest tenM

Round 2,740 to the nearest thousandI

Round 1,108 to the nearest hundredL

Round 31 to the nearest tenH

Round 73 to the nearest tenN

Round 17 to the nearest tenP

Round 706 to the nearest hundredV

Round 372 to the nearest tenR

Round 5,091 to the nearest thousandC

Round 7,119 to the nearest thousandD

Round 468 to the nearest hundredS

Round 227 to the nearest tenA

Round 851 to the nearest hundredE

Round 427 to the nearest tenO

Round 169 to the nearest tenU

0/16 letters found

Clue 2

Word problems

The ship spyglass scale rounds distances to the nearest league.

Solve each problem to learn its letter, then write the letters in the boxes to fill in the missing word.

Awitnesssawthevillainwas

There were 76 gold doubloons. 37 were used up. How many gold doubloons are left?R

There were 65 cannonballs. 10 were used up. How many cannonballs are left?A

There were 59 ship compasses. 8 were used up. How many ship compasses are left?T

Quartermaster Barnaby found 40 gold doubloons yesterday and 24 more today. How many gold doubloons in all?G

Quartermaster Barnaby lined up 4 rows of 12 treasure chests. How many treasure chests in all?I

Quartermaster Barnaby lined up 7 rows of 9 treasure chests. How many treasure chests in all?N

There were 68 treasure chests. 26 were used up. How many treasure chests are left?H

0/7 letters found

Clue 3

Addition

You add up all the recovered gold doubloons on deck.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

9538

7018

7402

7581

7646

6909

6027

4830

4456

5903

8929

7581

7018

7402

7575

6262

9538

7881

6262

7646

6909

9538

6660

7897

6525

6262

6369

6027

6660

5865 + 3673 =T

2148 + 4761 =O

3836 + 4061 =Q

4063 + 3518 =C

2599 + 2231 =F

2133 + 4236 =W

2616 + 3646 =A

4144 + 4785 =N

3830 + 3745 =D

1542 + 2914 =L

4666 + 2352 =H

4139 + 1888 =K

2557 + 4845 =E

2416 + 4109 =U

4036 + 2624 =S

2696 + 3207 =I

2923 + 4958 =P

2665 + 4981 =R

0/18 letters found

Clue 4

Subtraction

You subtract the damaged barrels from the galley tally.

Solve each problem to learn its letter. Then write that letter in every box that shows the same number, and read the secret clue.

2956

6029

7423

8981

2956

8116

5673

2956

7474

5274

6329

1128

7474

5009

8981

4109

6329

1432

2956

8981

3158

3029

5009

5673

4100

3158

5009

8116

8981

5009

8116

5009

6856 - 3900 =E

7030 - 1001 =V

12518 - 4402 =N

9841 - 2418 =I

8575 - 1101 =S

3820 - 791 =L

9264 - 4255 =A

4290 - 190 =K

6833 - 2724 =R

5323 - 2165 =B

5506 - 232 =H

3014 - 1582 =P

9028 - 2699 =O

3252 - 2124 =W

11567 - 2586 =D

6888 - 1215 =C

0/16 letters found

Clue 5

Division facts (1-12) — the last clue

You divide the total ship rations equally among the sailors.

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

132 ÷ 12 = ?

60 ÷ 5 = ?

28 ÷ 7 = ?

40 ÷ 8 = ?

5 ÷ 5 = ?

2 ÷ 1 = ?

18 ÷ 3 = ?

6 ÷ 2 = ?

70 ÷ 10 = ?

90 ÷ 10 = ?

120 ÷ 12 = ?

Step 2 — cross out the sentence with each answer

1.The villain swung a wooden staff, then unrolled a map scroll.

2.The villain threw a grappling hook, then peered through a spyglass.

3.The villain rolled a heavy cannonball, then unrolled a map scroll.

4.The villain fired a rusty flintlock, then peered through a spyglass.

5.The villain fired a rusty flintlock, then climbed a rope ladder.

6.The villain fired a rusty flintlock, then checked a brass compass.

7.The villain fired a rusty flintlock, then dropped an iron anchor.

8.The villain rolled a heavy cannonball, then checked a brass compass.

9.The villain rolled a heavy cannonball, then peered through a spyglass.

10.The villain swung a wooden staff, then dropped an iron anchor.

11.The villain threw a grappling hook, then climbed a rope ladder.

12.The villain rolled a heavy cannonball, then climbed a rope ladder.

Solve it

Name the culprit

Choose the one suspect left standing.

Answer Key — The Mystery of Barnacle Bay

Culprit: Grace O Malley (Cannonball · Brass Compass · Right Handed · Black Bandana · Parrot Squawks)

Clue 1 (Rounding): "THE VILLAIN DOES NOT USE A MAP SCROLL"
Round 127 to the nearest ten = 130 (T) · Round 51 to the nearest ten = 50 (M) · Round 2,740 to the nearest thousand = 3000 (I) · Round 1,108 to the nearest hundred = 1100 (L) · Round 31 to the nearest ten = 30 (H) · Round 73 to the nearest ten = 70 (N) · Round 17 to the nearest ten = 20 (P) · Round 706 to the nearest hundred = 700 (V) · Round 372 to the nearest ten = 370 (R) · Round 5,091 to the nearest thousand = 5000 (C) · Round 7,119 to the nearest thousand = 7000 (D) · Round 468 to the nearest hundred = 500 (S) · Round 227 to the nearest ten = 230 (A) · Round 851 to the nearest hundred = 900 (E) · Round 427 to the nearest ten = 430 (O) · Round 169 to the nearest ten = 170 (U)
Clue 2 (Word problems): "RIGHT HANDED"
There were 76 gold doubloons. 37 were used up. How many gold doubloons are left? = 39 (R) · There were 65 cannonballs. 10 were used up. How many cannonballs are left? = 55 (A) · There were 59 ship compasses. 8 were used up. How many ship compasses are left? = 51 (T) · Quartermaster Barnaby found 40 gold doubloons yesterday and 24 more today. How many gold doubloons in all? = 64 (G) · Quartermaster Barnaby lined up 4 rows of 12 treasure chests. How many treasure chests in all? = 48 (I) · Quartermaster Barnaby lined up 7 rows of 9 treasure chests. How many treasure chests in all? = 63 (N) · There were 68 treasure chests. 26 were used up. How many treasure chests are left? = 42 (H)
Clue 3 (Addition): "THE CROOK FLINCHED AT PARROT SQUAWKS"
5865 + 3673 = 9538 (T) · 2148 + 4761 = 6909 (O) · 3836 + 4061 = 7897 (Q) · 4063 + 3518 = 7581 (C) · 2599 + 2231 = 4830 (F) · 2133 + 4236 = 6369 (W) · 2616 + 3646 = 6262 (A) · 4144 + 4785 = 8929 (N) · 3830 + 3745 = 7575 (D) · 1542 + 2914 = 4456 (L) · 4666 + 2352 = 7018 (H) · 4139 + 1888 = 6027 (K) · 2557 + 4845 = 7402 (E) · 2416 + 4109 = 6525 (U) · 4036 + 2624 = 6660 (S) · 2696 + 3207 = 5903 (I) · 2923 + 4958 = 7881 (P) · 2665 + 4981 = 7646 (R)
Clue 4 (Subtraction): "EVIDENCE SHOWS A DROPPED BLACK BANDANA"
6856 - 3900 = 2956 (E) · 7030 - 1001 = 6029 (V) · 12518 - 4402 = 8116 (N) · 9841 - 2418 = 7423 (I) · 8575 - 1101 = 7474 (S) · 3820 - 791 = 3029 (L) · 9264 - 4255 = 5009 (A) · 4290 - 190 = 4100 (K) · 6833 - 2724 = 4109 (R) · 5323 - 2165 = 3158 (B) · 5506 - 232 = 5274 (H) · 3014 - 1582 = 1432 (P) · 9028 - 2699 = 6329 (O) · 3252 - 2124 = 1128 (W) · 11567 - 2586 = 8981 (D) · 6888 - 1215 = 5673 (C)
Clue 5 (Division facts (1-12)): surviving statement (box 8) → Grace O Malley
132 ÷ 12 = 11 · 60 ÷ 5 = 12 · 28 ÷ 7 = 4 · 40 ÷ 8 = 5 · 5 ÷ 5 = 1 · 2 ÷ 1 = 2 · 18 ÷ 3 = 6 · 6 ÷ 2 = 3 · 70 ÷ 10 = 7 · 90 ÷ 10 = 9 · 120 ÷ 12 = 10

About this mystery

Grade level: Grade 4 math
Math topics: Rounding, Word problems, Addition, Subtraction, Division
Reading level: grades 3-4
Theme: The Mystery of Barnacle Bay — set in Scurvy Cove
Format: Interactive online & printable worksheet with answer key
Solution: One unique, verified culprit among 21 suspects

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