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The unknown Dollar

A boy lends 100 dollars from his parents.He goes to a shop and buys something that costs 97 dollars,3 dollars are left.He gives one 1 dollar back to his mom,one to his dad and takes one for himself.Now he owes 49 dollars to his mom and 49 dollars to his dad,the addition of 49 and 49 equals to 98 dollars.He also had taken 1 dollar to himself,the addition of al the money is 99 dollars.So where is the other DOLLAR?






what are you talking about? There is no missing dollar! He spent 97 dollars in the shop and gave himself 1 so that is a total of 98 dollars - 49 owed to each of his mom and dad! So if you can explain what missing dollar you are talking about?!


Well done Sumsum from Iraq. As a piece of English writing you have done well.

As this is an English language website I will tackle the English, not the maths.  A BOY BORROWS $100 FROM HIS PARENTS. His parents LEND him the money. (You could use the passive: A boy IS LENT money BY his parents)  BORROW/LEND often causes problems. If I BORROW money I must give it back sometime. If I LEND money I WORRY I WON'T GET IT BACK! We have a saying, "Neither a lender nor a borrower be!" (Don't borrow money from people and don't lend it to them) Good advice!


You started to subtract the money he had paid them from $100, then added the money he had back on. Your maths really only used $3.


If you subtract the money he had paid them from $100, then  he still owed the amount of money remaining. From there you need to subtract , not add. So





He owed his parents $100, paid each $1 and so still owed $98. Instead of adding $1 back on, you need to subtract it ie. so if he paid his $1, he'd still owe $97. That's the money he'd spent buying something, so it all fits.







After coming back.

He owes 49+49=98 and he had taken 1 dollar to himself.49+49+1=99

but he had 100 dollars before going to the shops,where's that missing dollar?

you are mixing what the boy has and what the boy owes

the boy has something worth 97 dollars and 1 dollar (TOTAL of 98 dollars)

the boy owes his mother 49 dollars and his father 49 dollars (TOTAL of 98 dollars)


sum sum as I've explained to you there is no missing dollar. There is only bad arithmetic. Let me change your 'problem' slightly:


A boy borrows 100 dollars from his parents. He goes to a shop and spends 97 dollars there. There a 3 dollars left. He buys a bar of chocolate for 1 dollar and returns 2 dollars to his parents.


Now tell me is there still a missing dollar?


Alternatively you could change your 'problem' to this:


A boy borrows 100 dollars from his parents (50 each from his mom and his dad). He goes to a shop and spends 3 dollars. There are 97 dollars left. He keeps 1 dollar and gives 48 dollars each to his mom and dad. Now he owes 2 dollars each to his mom and dad. The addition of 2 dollars and 2 dollars makes 4 dollars and he has 1 dollar himself which makes a total of 5 dollars. So where are the missing 95 dollars?


As you see you can do anything with bad arithmetic!

He owed 48,5 dollars to mom and to 48,5 dollars to dad = 97, which he spent for shoppings, plus 1 dollar for him, one dollar for mom and one dollar for his dad = total 100 dollars.

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