Math Is Fun Forum

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Oral puzzles

Hi ganesh;

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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: Oral puzzles

hi ganesh

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“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: Oral puzzles

Hello

Last edited by Denominator (2011-08-14 07:25:27)

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anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Oral puzzles

hi Denominator

are you sure that your formula for the height of the triangle is okay?

---

“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: Oral puzzles

I don't know actually :\
But doesn't altitude mean perpendicular height
And if so, you would have to use pythagorean theorem to work it out?!?

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anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Oral puzzles

yes you can but it still doesn't explain the √5 part.

Last edited by anonimnystefy (2011-08-14 07:20:13)

---

“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: Oral puzzles

Oh you are right!
I treated 3√3 as one of the short sides which gave me a different answer
Thanks
I really need to check my work :\

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anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Oral puzzles

you're welcome.keep an eye on those things.

---

“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: 48,410

Re: Oral puzzles

Hi bobbym, Denominator, and anonimnystefy,

The solution #1176 is correct. Well done!

#1177. Find the compound interest on $15,625 for 9 months at 16% per annum compounded quarterly.

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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: Oral puzzles

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: 48,410

Re: Oral puzzles

Hi bobbym,

#1178. Albert invested an amount of $8000 in  a fixed deposit scheme for 2 years at compound interest rate 5% per annum. How much amount would Albert get on maturity of the fixed deposit?

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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: Oral puzzles

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: Oral puzzles

Sorry, what does maturity mean?

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bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Oral puzzles

Hi;

In this case when the terms of the deposit scheme are over ( 2 years ).

---

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: Oral puzzles

Oh okay,
Thanks
I don't know much of the bank terms :s

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Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,410

Re: Oral puzzles

Hi bobbym and Denominator,

The solution #1178 is perfect. Neat job!

#1179. What would be the compound interest on a sum of $25,000 after 3 years at the rate of 12% per annum?

---

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: Oral puzzles

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: Oral puzzles

I get

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Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,410

Re: Oral puzzles

Hi bobbym and Denominator,

The solution #1179 (Principal + Interest) is correct. Well done!

#1180. Sam invests $15,000 @ 10% per annum for one year. If the interest be compounded half-yearly, then what is the amount he received at the end of one year?

---

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: Oral puzzles

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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,410

Re: Oral puzzles

Hi bobbym,

The solution #1180 is correct. Good work!

#1181. The radius and the height of a right circular cone are in the ratio 5:12. If its volume is 314 cubic meters, find the radius and slant height. (Use

)

---

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: Oral puzzles

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: 48,410

Re: Oral puzzles

Hi bobbym,

The solution #1181 is correct. Well done!

#1182. A sector containing an angle of 90[sup]o[/sup] is cut from a circle of radius 20 cm and folded into a cone. Find the curved surface area of the cone.

---

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: Oral puzzles

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.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,410

Re: Oral puzzles

Hi bobbym,

#1183. A hemisphere is of radius 9 cm. Find the volume and the curved surface area.

---

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.