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## #6601 2020-03-30 00:34:18

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4745. A bag contains 7 blue balls and 5 yellow balls. If two balls are selected at random, what is the probability of none is yellow?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6602 2020-04-01 00:29:11

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4746. A die is thrown twice. What is the probability of getting a sum of 7 from both the throws?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6603 2020-04-03 00:23:53

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4747. In a box, there are 8 red, 7 blue, and 6 green balls. One balls is picked up randomly. What is the probability of it being neither blue nor green?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6604 2020-04-05 00:20:00

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4748. A bag contains 4 red, 5 yellow, and 6 pink balls. Two balls are drawn at random. What is the probability of none of the balls being drawn are yellow?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6605 2020-04-07 00:09:45

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4749. A bag contains 5 red, 7 yellow, and 3 pink balls. If two balls are drawn at random from the bag, one after the other, what is the probability of the first ball being red, and the second ball being yellow?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6606 2020-04-09 00:45:16

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4750. A box contains 14 eggs out of which 8 are rotten. Two eggs are chosen at random. What is the probability of none of the eggs being rotten?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6607 2020-04-11 00:16:09

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4751. In a bag, there are 6 red balls, 4 green balls, and 8 yellow balls. What is the probability of drawing one ball which is neither green nor yellow?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6608 2020-04-13 00:17:59

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4752. A bag contains 13 white and 7 black balls. Two balls are drawn at random. What is the probability of they being of the same color?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6609 2020-04-15 00:06:31

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4753. A bag contains 3 red balls, 5 yellow balls, and 7 pink balls. If one ball is drawn at random from the bag, what is the probability of it being either pink or red?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6610 2020-04-17 00:32:09

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4754. A bag contains 7 blue balls and 5 yellow balls. If two balls are selected at random, what is the probability of neither of them being yellow?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6611 2020-04-19 00:04:28

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4755. How many terms are there in an Arithmetic Progression 10, 12, 14, 16, ......., 80?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6612 2020-04-21 00:03:59

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4756. In an Arithmetic Progression 1, 3, 5, ..., which term of this Arithmetic Progression is 155?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6613 2020-04-23 00:09:34

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4757. Find the 15th term of the sequence : 20, 15, 10, ....

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6614 2020-04-25 00:03:13

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4758. Find the sum of last 5 terms of the series 3, 8, 13, ....., 103.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6615 2020-04-27 00:07:12

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4759. Find the value of the expression 1 - 6 + 3 - 10 + 5 - 14 + 7 - 18 + .... up to 100 terms.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6616 2020-04-29 00:20:09

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4760. Find the value of 50 terms of

.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6617 2020-05-01 00:24:14

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4761. A number 27 is divided into three parts which are in Arithmetic Progression and the sum of their squares is 261. Find the smallest one.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6618 2020-05-03 00:22:28

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4762. A sum of money kept in a savings bank account amount to \$1240 in 4 years and \$1600 in 10 years. Find the sum (simple interest).

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6619 2020-05-05 00:10:17

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4763. Robert receives \$600 in the first week and \$30 more each week than the preceding. What does he get in the 20th week?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6620 2020-05-08 00:14:13

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4764.  Robert receives \$600 in the first week and \$30 more each week than the preceding. What is the total amount he has received by the end of the 20th week?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6621 2020-05-10 00:16:59

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4765. Find the least value of n for which the sum of the series 5 + 8 + 11 + ... up to n terms is not less than 670.
(a) 20
(b) 21
(c) 22
(d) 23.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6622 2020-05-12 00:07:29

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4766. How many natural numbers between 100 and 400 are there which are multiples of 9?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6623 2020-05-14 00:59:32

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

.

#4767. Find the number of terms in the series 15 + 13 + 11 + 9 + 7 + 5+ ...... such that the sum is 63. If there are two solutions, give both.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6624 2020-05-16 00:02:21

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4768. Find the least value of n for which the sum of the series 3 + 7 + 11 + 15 + 19 + ... is greater than 820.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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## #6625 2020-05-18 00:32:59

ganesh
Registered: 2005-06-28
Posts: 30,317

### Re: Oral puzzles

Hi,

#4769. The average of 50 numbers is 38. If two numbers viz. 45 and 55 are discarded, find the average of the remaining numbers.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

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

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