Explore the tricky “$50 from Mum, $50 from Dad” riddle. If you borrow $50 from each parent to buy a $97 item, where does the missing dollar go? Learn how this clever riddle works and uncover the math behind the illusion.

The “$50 from Mum, $50 from Dad” Riddle Explained: Where is the Missing Dollar?

Riddle Overview:

The riddle goes as follows:

  1. You borrow $50 from Mum and $50 from Dad, giving you a total of $100.
  2. You buy a bag costing $97, leaving you with $3.
  3. You return $1 to Mum and $1 to Dad, keeping $1 for yourself.
  4. Now, you owe $49 to each parent (since you paid back $1 to each).
  5. According to the riddle, you now owe $49 + $49 = $98, and if you add the $1 you kept, it seems to total only $99.

The question is: Where is the missing dollar?

The answer lies in understanding the logical flow and math behind this riddle. Let’s break it down step-by-step to uncover the solution.

Step-by-Step Solution to the Riddle

  1. Starting with $100:
    • You initially have $100 after borrowing $50 from each parent.
  2. Buying the Bag:
    • You purchase a bag for $97, which leaves you with $3 in change.
  3. Returning $1 to Each Parent:
    • You decide to return $1 to Mum and $1 to Dad, so you have now repaid $2 of your debt.
    • After repaying $1 each, you owe $49 to Mum and $49 to Dad.
  4. The Misleading Calculation:
    • The riddle says you owe $49 + $49 = $98, and adding the $1 you kept makes it $99. This misleadingly suggests a dollar is missing from the original $100.
  5. Breaking Down the True Accounting:
    • The mistake lies in how the numbers are combined. Instead of adding the $1 you kept to the remaining debt, you should consider it as part of the $100 balance.
    • Here’s the correct breakdown:
      • Debt owed: $98 in total ($49 to each parent).
      • Cash on hand: $1.
      • Together, the debt and remaining cash account for the full $100 you initially borrowed.

Why There is No Missing Dollar

The riddle tricks you into thinking you should add the $1 you kept to the $98 debt, but in reality, they should be separate figures in the equation. When you look at it correctly:

  • $98 debt + $1 cash = $99 is irrelevant; it just confuses the accounting.
  • The actual calculation is $100 borrowed – $97 spent = $3 in change, which is fully accounted for.

Final Answer:

There is no missing dollar. The apparent discrepancy arises from combining unrelated numbers, tricking us into an unnecessary calculation.

This riddle is an excellent example of how assumptions in math can lead us down the wrong path, making it a fun challenge in logical thinking and basic accounting!

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Riddles,