日本語
Splitting the Bundles of Cash (illustration)
FILE No.182Unsolved

Splitting the Bundles of Cash

Difficulty ★★☆about 5 minLogic PuzzleLeast common multipleRemainders
Divided among 7, 2 bundles are short; also 2 short with 5 or with 3 people. What is the smallest number of bundles?

Case Record

A gang of robbers tried to split bundles of cash evenly. Dividing evenly among 7 people leaves them 2 bundles short. After some left and there were 5 people, they were still 2 bundles short, and with 3 people they were again 2 bundles short.

Your question

What is the smallest possible number of bundles?

Case Files

Diagram

The "2 short" conditionsPeopleResult72 short52 short32 shortWhat is the smallest number of bundles?
Diagram

Hints

If you get stuck, open the hints one at a time, in order.

Open hint 1

What does "2 short" mean in terms of adding 2 bundles?

Open hint 2

Think about numbers divisible by 7, 5, and 3.

Open hint 3

What is the smallest such number?

Solve It

Your question

What is the smallest possible number of bundles?

Choose the answer closest to the truth.

Share: I'm solving this

The Truth

103 bundles

The answer is "103 bundles."

"2 bundles short" means "with 2 more bundles, it would divide evenly." The smallest number divisible by 7, 5, and 3 is 7 × 5 × 3 = 105. Subtracting 2 gives 103 bundles, which meets the conditions.

105 bundles would divide evenly, so it would not be "short." 98 is divisible by 7, but it is not "2 short" for 5 (98 + 2 = 100 is not divisible by 7).

Adding 2 makes every split exactItemDetailConditionBundles + 2 is a multiple of 7, 5 and 3LCM7 × 5 × 3 = 105Bundles105 − 2 = 103
Diagram of the solution

Key Points

  • Rephrase "short" as "divisible if you add"
  • Use the least common multiple
  • Subtract 2 and check

Why people get fooled

Because it is easy to mistake "2 short" for "a remainder of 2."

Similar tricks

    If you like this file, try these

    The Barbecue Bill (illustration)The Barbecue Bill★★☆about 5 minThe Trains and the Bird (illustration)The Trains and the Bird★★☆about 5 minTimes Four, Reversed (illustration)Times Four, Reversed★★☆about 5 minTen in a Circle (illustration)Ten in a Circle★★☆about 5 min

    If you view the truth, this case will not count as solved on your own. Open it anyway?

    Privacy Policy

    The cases on this site are fictional puzzles created for entertainment. Any resemblance to real people, organizations or events is coincidental.

    © Unsolved Files