Math Is Fun Forum

zetafunc

Moderator

Registered: 2014-05-21

Posts: 2,436

Website

Re: Oral puzzles

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: 48,406

Re: Oral puzzles

Hi,

The solution #2509 is perfect! Good work, zetafunc and bobbym!

#2510. Solve :

hence the value of 'p' if y = px - 2.

---

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.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Oral puzzles

---

Only a friend tells you your face is dirty.

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: 48,406

Re: Oral puzzles

Hi,

The solution #2510 is correct, math9maniac and bobbym! Brilliant!

You have missed the latter part of the problem

, math9maniac!

#2511. The incomes of X and Y are in the ratio 8:7 and their expenditures are in the ratio 19:16. If each saves $1250, find their incomes.

---

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: 48,406

Re: Oral puzzles

Hi bobbym,

The solution #2511 is perfect! Excellent!

#2512. Points 'A' and 'B' are 70 kilometers apart on a highway. A car starts from 'A' and another car starts from 'B' simultaneously. If they travel in the same direction, they meet in 7 hours, but they travel towards each other, they meet in one hour. Find the speed of the two cars.

---

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: 48,406

Re: Oral puzzles

Hi bobbym,

The solution #2512 is correct! Good work!

#2513. The ratio of incomes of two persons is 9:7 and the ratio of their expenditures is 4:3. If each of them saves $200 per month, find their monthly incomes.

---

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: 48,406

Re: Oral puzzles

Hi bobbym,

The solution #2513 ( both parts) is correct! Neat work!

#2514. Find the condition that the point (x,y) may lie on the line joining (3,4) and (-5,-6).

---

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.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Oral puzzles

---

Only a friend tells you your face is dirty.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,406

Re: Oral puzzles

Hi math9maniac,

#2515. Evaluate :

.

---

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.

zetafunc

Moderator

Registered: 2014-05-21

Posts: 2,436

Website

Re: Oral puzzles

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,406

Re: Oral puzzles

Hi zetafunc,

#2516. Two customers are visiting a particular shop in the same week (Monday to Saturday). Each is equally likely to visit the shop on any one day as on another.  What is the probability that both will visit the shop on
(i) the same day?
(ii) different days?
(iii) consecutive days?

---

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: 48,406

Re: Oral puzzles

Hi bobbym,

#2517. Find the probability that a number selected at random from the numbers 1, 2, 3, ....35 is a
(i) prime number
(ii) multiple of 7
(iii) multiple of 3 or 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.

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: 48,406

Re: Oral puzzles

Hi bobbym,

The solution #2517 (all three parts) is/are correct! Good work!

#2518. Find the probability of a number selected from 1 to 25 is not a prime number then each of the given numbers is equally likely to be selected.

---

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: 48,406

Re: Oral puzzles

Hi bobbym,

The Solution #2518 is correct! Smart work!

#2519. Find the numbers a, b, c between 2 and 18 such that their sum is 25. The numbers 2, a, b are in Arithmetic Progression and the numbers b, c, 18 are Geometric Progression.

---

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.

math9maniac

Member

From: Tema

Registered: 2015-03-30

Posts: 443

Re: Oral puzzles

---

Only a friend tells you your face is dirty.

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,406

Re: Oral puzzles

Hi math9maniac,

The solution #2519 is perfect! Excellent, math9maniac!

#2520. The first term of a Geometric Progression is 64 and the common ratio is 'r'. Find 'r' if the average of the first and fourth terms is 140.

---

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.