You saw a laptop of 97k.
You didn't have the cash,
So you borrowed 50k from your mum
and 50k from your dad = 100k.
You bought the laptop which left you with 3k change.
You gave your mum 1k and your dad 1k and used the other 1k for transport.
Now, you are owing your mum 49k and your dad 49k.
Now 49k + 49k = 98k + your 1k transport = 99k.
Where is the missing 1k