A question has been doing rounds on social media.
"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?," reads the question.
The missing dollar has intrigued several internet users.
While going forward with the calculation from the point where the kid borrowed the money one dollar is missing.
“This is a counting trick”
"The problem with the question is that it is not clear what we are trying to calculate. Is it the amount of money you owe? Or is it the amount of money spent? The amount you have? The final calculation is sort of a combination of each. Owe + owe + have = does not make sense. What we are looking for, then, is where the money went. 49 came from Mom, 49 came from Dad. 97 went to the shop. 1 went to you. 49 + 49 = 97 + 1. Solved!," explains one Quora user.
Brain teaser: 8 most mind-twisting puzzles for you to solve (with answers)
"You have the wrong perspective. You took $100, you paid back $2, effectively borrowing $98. You spent $97 of that $98 leaving you $1 change. There is no missing $1, you only appear to have a missing $1 because your perspective is incorrect. The $1 you reserved yourself is part of the $98, not additional to the $98. The other $2 you repaid so it's no longer part of the equation," explains another.
Mathematics teacher, Rachel Frasier, who had shared this question in 2019 on Twitter, explains: "There is no missing dollar! You started with $100 and spent $97. With the $3 left, you gave $1 to mom, $1 to dad, and kept $1. You owe them $98 but kept $1, which you can count towards what you owe them. So, you need $97 more to pay them back (cost of shirt)! “
To this another Twitter user explains: "The part of this that trips people up I think is the last bit, which is technically incorrect: "together that's $98. Plus the $1 I kept is $99" because it's a debt of $98, so an extra dollar actually nets $97 not 99, which is the money that was spent on the shirt and checks out."
"You're adding up debt as cash.
Let's look at how much money each party had at each step.
You Mom Dad Store. Total
$0. $50. $50. $0. $100
$100. $0. $0. $0. $100
$3. $0. $0. $97. $100
$1. $1. $1. $97. $100
The total amount of money never changed," explains another.
What is your explanation for this
riddle
?
Mathematics riddles as such have always been intriguing. People engage in solving these puzzles and end up several discussions. These riddles are solved using several theories and it is interesting to know how a single problem can be solved in various ways.
Benefits of solving riddles
Riddles are fascinating and also evoke a sense of curiosity in us. But apart from that, solving riddles, brain teasers, puzzles can improve our memory, focus, problem-solving abilities and decrease stress levels. These are great pass times that also enhance our cognitive abilities. It won't be wrong to say that brain teasers are the fun way to estimate our understanding of a problem.
Along with children, math riddles can also be challenging for adults, especially since they might have forgotten their way around numbers and tricky calculations. In fact, sometimes these may be easier for students as they are more in the habit of solving troubling math problems.
That said, stay tuned for more of these and test your brain!
FAQs
The correct way to sum up the total would be $10 in the register, plus $2 in the bellhop's pocket, plus $6 for each guest, which is indeed $30. Another way to look at it is this: The guests didn't each pay $9, they paid $8.333 dollars and then received $1 each. So $8.333 x 3 = $25, and $25 + $3 + $2 = $30.
What is the answer to the 30$ riddle? ›
Each of the 3 guests has $1 in his pocket, totaling $3. When added to the $27 revised cost of the room (including tip to the bellhop), the total is $30. To obtain a sum that totals to the original $30, every dollar must be accounted for, regardless of its location. This sum does indeed come out to $30.
What is the answer to the riddle you buy a shirt for $97 dollars? ›
Mathematics teacher, Rachel Frasier, who had shared this question in 2019 on Twitter, explains: "There is no missing dollar! You started with $100 and spent $97. With the $3 left, you gave $1 to mom, $1 to dad, and kept $1. You owe them $98 but kept $1, which you can count towards what you owe them.
What is the answer to the three friends riddle? ›
Our Solution:
When the friends paid $10 dollars, they had paid $30 in total. When the Cashier gave $5 dollars to the Waiter, the 3 friends had paid $25 to the Cashier and $5 to the Waiter. When the Waiter returns 3 dollars, the 3 friends had paid $25 to the Cashier and $2 to the Waiter. $25+$2 = $27 = 3 x $9.
Where is the missing dollar solution? ›
Solution. There is no missing dollar. You cannot add the manager's $2 to the $27 that the three friends paid, because how much they paid already includes it – this would be double-counting. The three friends ended up paying $27, including $25 to the hotel and $2 to the manager, which adds up.
How do you solve a riddle answer? ›
Break the riddle down into parts to solve it in chunks.
Consider what each chunk of the riddle is trying to convey, and then piece them back together to help flesh out your answer. Once you have a better understanding of the pieces, it'll be a lot easier to eliminate wrong answers.
Where is the missing dollar riddle 100? ›
You took $100, you paid back $2, effectively borrowing $98. You spent $97 of that $98 leaving you $1 change. There is no missing $1, you only appear to have a missing $1 because your perspective is incorrect. The $1 you reserved yourself is part of the $98, not additional to the $98.
What is a riddle question? ›
A riddle is a fun type of brain teaser that exists as a question or statement to be solved. Usually, riddles are worded in a puzzling or misleading way. Many have a double or hidden meaning that requires creative, outside-the-box thinking.
What has 15 diamonds but isn t rich? ›
Riddle: What has fifteen diamonds but isn't rich? Answer: A deck of cards.
What has many keys but can't buy? ›
Answer: Option (D) Piano
The Piano has many keys but can't open a single lock. The given question is ''What has many keys but can't open a single lock?''
Riddle Explained
Let's make this as simple as possible: The man stole a $100 bill to begin with—so that is what the shop owner had lost. The man used that $100 to buy $70 worth of stuff, which means the shop owner had to provide $30 in change from the register to complete the transaction.
What is there one if in every corner and two in every room? ›
6) Riddle: What is there one of in every corner and two of in every room? Answer: The letter 'o'. Explanation: The word 'corner' has one 'o' in; the word 'room' has two 'o's in.
What has many keys but can't open the door answer? ›
Answer: “A Piano” is the correct answer. A piano is a musical instrument with many keys but can't open a single lock. A keyboard is another answer to this. It has keys but no locks.
What has to be broken before you can use it? ›
Answer: Egg.
The answer to the riddle “What has to be broken before you can use it?” is an Egg. Because The Egg must be broken to be Cooked, eaten, or Hatched.
What to do with the dollar in riddle School? ›
The money in this game is only a dollar given by Janitor. It is used to move Chubb.
Where is the dollar in riddle school? ›
Dollar - It is obtained from 808 after giving him his Feather Duster. It is used to move Chubb away. It occupies the third slot.
