I borrowed $50 from mum and $50 from dad

 Let’s break down the situation step by step:

1. You borrowed $50 from your mum and $50 from your dad, totaling $100.
2. You used this $100 to buy a bag costing $97.
3. After the purchase, you had $3 left.

Now let’s account for the money you returned to your parents and the dollar you reserved for yourself:

• You returned $1 to your dad and $1 to your mum, which makes it a total of $2.
• You also reserved $1 for yourself.

Adding these up:

• $97 (bag) + $2 (returned) + $1 (reserved) = $100.

So there is no missing dollar. The total amount still adds up to the original $100 you borrowed. The confusion arises from the way the question is framed, but mathematically, everything balances out! 😊