# Math riddles with answers: Henry found these hard math riddles in his strange old diary. Can you solve them?

*Henry’s diary and math riddles!*

When was the last time you cleaned your room and cupboards? No, we are not trying to teach you a lesson or two on cleanliness, organization, and space management. This was just an innocent question we intended to ask you. When was the last time you actually cleaned your room?

Well, cleaning a room is a tiring task, but the fun part of it is that oftentimes you can switch on your favorite music and dance your heart out with the dusty ornaments in your room while cleaning them. Another exciting thing about cleaning a room that occurs not every time but only on days we are lucky is that we may find something so old that we forget it ever existed in our lives.

So what feeling do these things from our past erose? Well, that is a difficult question to answer. While all these definitely give rise to a strange bittersweet feeling, some things may make you wonder why you ever found them again. For instance, a rose given to you by someone you loved dearly but do not have by your side today may give you flashbacks firstly of the good memories shared with them and then of the sad ending. However, on the other hand, in case you find something from your childhood, like your favorite toy, your most loved Barbie doll, a bracelet given to you by your childhood friend, your favorite bedsheet, or your childhood clothes, the very glance of these objects will bring a wide smile and a sense of excitement to your face. Such is the nature of old memories!

Well, while finding old objects can mostly elicit either good or bad memories, sometimes, some objects trick us for hours. This is something that happened with Henry today. Let’s find out.

**Henry, his school diary, and math riddles- STORY TIME!**

Henry is a 25-year-old software engineer who works in a reputed company and earns a handsome salary. All his life he has been extremely hardworking and managed to score great academic success. When he was in school, he was one of the favorites of his teacher. However, in the primary standards of his school, he struggled hard to manage math as a subject. *Who cares? He worked hard on the subject, sharpened his skills, and today has become a successful software engineer!*

Well, that is not the point we are trying to make. Today, when he decided to clean his cupboard, he accidentally found a diary that had his school name written on it. When he opened it, he found his own name written on it in childlike handwriting.

**Image Source: IndiaMART**

Everything was good until now till he flipped the pages. On the first page, he found the sketch of his favorite cartoon from childhood. Henry was definitely good at sketching back in school, but cannot recall the exact moment when he drew this sketch. On the second page, the guy found some random scribbling which he did not pay attention to. On the third page was something really exciting yet astonishing.

On the third page wrote,

**“Whether I am 10 or 25, I am still never going to solve these HARD math riddles.”**

**“Whether I am 10 or 25, I am still never going to solve these HARD math riddles.”**

The statement made Henry go in shock. Probably when he wrote this statement, he may be a 10-year-old child. However, does this means that the 10-year-old Henry actually challenged the present-day Henry in advance? This sounded strange, and even a little horrifying!

Henry immediately flipped the pages and found some math riddles written.

Now, the super intelligent guy is a bit nervous, as his younger self has all-of-a-sudden challenged him. Can you help Henry solve these math riddles?

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**Math riddles in Henry’s diary:**

**Math riddle 1:**

Liam asks for $50 from his dad and $50 from his mom, and his parents give him the demanded money. Now, this means he has $100. With this money, he moves to a shop and purchases a blazer worth $97. Now, with the $3 left with him, Liam gives $1 to his dad and $1 to his mom, while keeping $1 with himself. This means Liam owes his dad $49 and his mom $49, together this makes $98. Now, the $1 he kept makes it $99. Where has the other dollar gone?

**Math riddle 2:**

Susan had a set of new faucets installed in her house. However, the speed of the two faucets is different from each other. The hot faucet that Susan installed fills the bath at a specific rate which is 15 liters per minute. On the other hand, the cold faucet in Susan’s bath lets the water in at a specific rate which is 10 liters per minute. If we talk about the plug hole, then it allows the water out of the bath at a specific rate too, which is 12 liters per minute.

Now, the bath can hold a maximum of 520 liters.

If one fine day, Susan turns both the hot and cold faucets on, but somehow misses putting the plug in, how much time in minutes will it require for the bath to actually overflow?

(PS: Don’t be a careless fellow like Susan and always try to save water!)

**Math riddle 3:**

When Gracy was 6 years old, her brother John was actually half her age. If today, Gracy cuts her 50th birthday cake, what according to you is the age of her brother?

After solving the third math riddle, Henry accidentally flipped a few more pages that contained random scribbling, until he reached the very last page, where he found something even more strange.

The last page read:

**“Answers for the 25-year-old Henry”. **

**“Answers for the 25-year-old Henry”.**

The statement was written by the 10-year-old Henry in his childlike handwriting. Followed by the statement were the answers to the math riddles

**“Answers for the 25-year-old Henry”**

**Math riddle 1:**

Liam asks for $50 from his dad and $50 from his mom, and his parents give him the demanded money. Now, this means he has $100. With this money, he moves to a shop and purchases a blazer worth $97. Now, with the $3 left with him, Liam gives $1 to his dad and $1 to his mom, while keeping $1 with himself. This means Liam owes his dad $49 and his mom $49, together this makes $98. Now, the $1 he kept makes it $99. Where has the other dollar gone?

**Answer 1:**

The punch here is that **there is actually no missing dollar at all!** Liam started with an amount of $100. He then spent $97 on the blazer. After buying the blazer, he is left with $3. He then gave $1 to his dad and $1 to his mom and kept $1 to himself. This means that Liam owes his parents $98, but since he has kept $1 to himself, which can be counted towards what Liam owes to them.

Thus, the guy needs $97 (the cost of the blazer) more to pay his parents.

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**Math riddle 2:**

Susan had a set of new faucets installed in her house. However, the speed of the two faucets is different from each other. The hot faucet that Susan installed fills the bath at a specific rate which is 15 liters per minute. On the other hand, the cold faucet in Susan’s bath lets the water in at a specific rate which is 10 liters per minute. If we talk about the plug hole, then it allows the water out of the bath at a specific rate too, which is 12 liters per minute.

Now, the bath can hold a maximum of 520 liters.

If one fine day, Susan turns both the hot and cold faucets on, but somehow misses putting the plug in, how much time in minutes will it require for the bath to actually overflow?

(PS: Don’t be a careless fellow like Susan and always try to save water!)

**Answer 2:**

The answer is **40 minutes.**

**EXPLANATION:**

The hot faucet is able to fill the bath at a rate of 15 liters per minute. On the other hand, the cold faucet is able to fill the bath at a rate of 10 liters per minute.

Now, water enters at a rate of 25 liters per minute. (How? Well, 15 added to 10 is 25.)

Moreover, the plug hole is able to empty at the rate of 12 liters per minute.

Thus, the bath fills up at the rate of 13 liters per minute. (How? Well, 12 subtracted from 25 is 13.)

Now, the bath holds 520 liters of water.

Thus, since 520 divided by 13 is 40, the bath overflowed at 40 minutes.

**Math riddle 3:**

When Gracy was 6 years old, her brother John was actually half her age. If today, Gracy cuts her 50th birthday cake, what according to you is the age of her brother?

**Answer 3:**

John is** 47 years old.**

When Gracy was 6, John was 3. This does not only mean that John was half her age. This also means that John was 3 years younger than Gracy.

Now, when Gracy is 50 years old and John is three years younger than his sister, he must be 47 years old today.*Were you able to help Henry solve these strange math riddles?*

And why did little Henry leave these math riddles for the 25-year-old present-day Henry to solve? This now sounds scary. While the math riddles were actually fun, some mysteries are better unresolved. It seems as if Henry finished a long-pending task today, that his little version left for him to complete years ago.

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