several wooden crates overflowing with oranges

Image: ©

Difficulty: Extreme!

These 2 brothers sold oranges for a living. On Monday:

  • Josh priced his oranges at 2 for $3. He sold 30 oranges for $45.
  • Zach priced his oranges at 3 for $4. He sold 30 oranges for $40.

On Tuesday, they combined their prices, and sold their oranges in groups of (2 + 3) 5 for ($3 + $4) $7.
At the end of the day, they sold (30 + 30) 60 oranges, and they expected to get ($45 + $40) $85 in total.

When they counted their money, they’d only made $84. What happened?
Scroll down or click for a hint, or the answer!

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Brainteaser hint

Think about how many oranges were sold by each brother.

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Brainteaser answer

Selling 5 oranges at the combined price is the same as selling 2 oranges at Josh’s price and 3 at Zach’s price. If they sold 60 oranges at the combined price, it’s the same as selling 12 groups of oranges (12 x $3 + 12 x $4 = $84). That’s 24 oranges at Josh’s price ($1.50 per orange), and 36 at Zach’s cheaper one (~$1.33 per orange), rather than 30 oranges each.

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