😊🧐🤔
I borrowed $50 from mum and $50 from dad to buy a bag costing $97.
After the purchase, I had $3 left.
I returned $1 to dad and $1 to mum, and reserved $1 for myself.
I now owe $49+$49=$98 plus the $1 I reserved for myself, which is $99.
Where is the missing $1?