Math Is Fun Forum

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym, anonimnystefy, and Denominator,

The solution #3122 is correct. Good work!

#3123. A man sells an article at a profit of 25%. If he had bought it at 20% less and sold it for $10.50, he would have gained 30%. Find the cost price of the article.

#3124. The price of a jewel, passing through three hands, rises on the whole by 65%. If the first and the second sellers earned 20% and 25% profit respectively, find the percentage profit earned by the third seller.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Denominator

Member

Registered: 2009-11-23

Posts: 220

Re: 10 second questions

I don't work very well with percentages but I hope this is right :]

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bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi Denominator and bobbym,

The solution #3124 is correct. Excellent!

Regarding #3123, I get $50.

#3125. A dealer sold three-fourth of his articles at a gain of 20% and the remaining at cost price. Find the gain earned by him in the whole transaction.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: 10 second questions

hi ganesh

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym and anonimnystefy,

The solution #3125 is perfect. Well done!

#3126. 1100 boys and 700 girls appeared for an examination; 42% of the boys and 30% of the girls were successful. What is the percentage of the total who failed?

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: 10 second questions

hi ganesh

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym and anonimnystefy,

The solution #3126 is correct. Good work!

#3127. The value of a machine depreciates at the rate of 10% per annum. If its present value is $162,000, what would be its worth after 2 years? What was the value of the machine 2 years ago?

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: 10 second questions

hi ganesh

---

“Here lies the reader who will never open this book. He is forever dead.
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

Denominator

Member

Registered: 2009-11-23

Posts: 220

Re: 10 second questions

Are we suppose to answer these in 10 seconds
I hardly can do it in 5 minutes with paper

Last edited by Denominator (2020-11-03 18:45:55)

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Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym, anonimnystefy, and Denominator,

The solution is

.

Outstanding, Denominator!

#3128. A man bought a horse and a carriage for $3000. He sold the horse at a gain of 20% and the carriage at a loss of 10%, thereby gaining 2% on the whole. Find the cost of the horse.

#3129. Find the single discount equivalent to a series discount of 20%, 10%, and 5%.

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

Denominator

Member

Registered: 2009-11-23

Posts: 220

Re: 10 second questions

Oh yay!

Last edited by Denominator (2011-08-11 18:32:55)

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bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi Denominator and bobbym,

The solutions #3128 and #3129 are correct. Excellent!

#3130. If 1 cubic cm of cast iron weighs 21 grams, then find the weight of a cast iron pipe of length 1 meter with a bore of 3 cm and in which thickness of the metal is 1 cm.

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym,

#3131. The radii of the bases of a cylinder and a cone are in the ratio 3:4 and their heights are in the ratio 2:3. Find the ratio of their volumes.

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

Hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Denominator

Member

Registered: 2009-11-23

Posts: 220

Re: 10 second questions

I think this is right...

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Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym and Denominator,

The solution #3131 is perfect. Well done!

#3132. If the numerator of a fraction is increased by 2 and the denominator is increased by 3, the fraction becomes

and if the numerator as well as the denominator are decreased by 1, the fraction becomes

. What is the original fraction?

#3133. 243 has been divided into three parts such that half of the first part, one-third of the second part and one-fourth of the third part are equal. Find the largest part.

---

It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: 10 second questions

hi ganesh;

---

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Denominator

Member

Registered: 2009-11-23

Posts: 220

Re: 10 second questions

Hello

I don't think my answers are right but worth a try :3

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Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,385

Re: 10 second questions

Hi bobbym and Denominator,

The solutions #3132 and #3133 are correct, bobbym. Neat job!

#3134. A man can row 18 km/hour in still water. It takes him thrice as long to row up as to row down the river. Find the rate of the stream.

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It appears to me that if one wants to make progress in mathematics, one should study the masters and not the pupils. - Niels Henrik Abel.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.