Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4770 and #4771 are correct. Good work!

#4772. A student was asked to find the arithmetic mean of the numbers 3, 11, 7, 9, 15, 13, 8, 19, 17, 21, 14 and x. He found the mean to be 12. What should be the number in place of x?

#4773. The average of 2, 7, 6 and x is 5 and the average of 18, 1, 6, x and y is 10. What is the value of y?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4772 and #4773 are correct. Fantastic!

#4774. If the mean of 5 observations x, x + 2, x + 4, x + 6 and x + 8 is 11, then find the mean of the last three observations.

#4775. If the mean of a, b, c is M and ab + bc + ca = 0, then what is the mean of a², b², c²?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4774 and #4775 are correct. Fantastic!

#4776. Find the average of first 50 natural numbers.

#4777. Find the mean of 1², 2², 3², 4², 5², 6², and 7².

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4776 and #4777 are correct. Neat work!

#4778. Find the average of all odd numbers up to 100.

#4779. If a, b, c, d, and e are five consecutive odd numbers, what is their average?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4778 and #4779 are correct. Good work!

#4780. The average of a non-zero number and its square is 5 times the number. Find the number.

#4781. The average of 7 consecutive numbers is 20. What is the largest of these numbers?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4780 and #4781 are correct. Immaculate!

#4782. The average of five consecutive odd numbers is 61. What is the difference between the highest and lowest numbers?

#4783. The sum of three consecutive odd numbers is 38 more than the average of these numbers. What is the first of these numbers?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4782 and #4783 are correct. Marvelous!

#4784. A library has an average of 510 visitors on Sundays and 240 on other days. What is the average number of visitors per day in a month of 30 days beginning with a Sunday?

#4785. If the average marks of three batches of 55, 60 and 45 respectively is 50, 55 and 0, then the average marks of all the students is ___________.

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solution #4784 is perfect. Excellent!

I have altered #4785 and included #4786.

#4785. If the average marks of three batches of 55, 60 and 45 students respectively is 50, 55 and 60, then the average marks of all the students is ___________.

#4786. The average weight of 16 boys in a class is 50.25 kilograms and that of the remaining 8 boys is 45.15 kilograms. Find the average weight of all the boys in the class.

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

Thanks for rewriting the problem.

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4785 and #4786 are correct. Exemplary!

#4787. A car owner buys petrol at $7.50, $8.00, and $8.50 per liter for three successive years. What approximately is the average cost per liter of petrol if he spends $4000 each year?

#4788. Out of 9 persons, 8 persons spent $30 each for their meals. The ninth one spent $20 more than the average expenditure of all the nine. What is the total money spent by all of them?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4787 and #4788 are perfect. Remarkable!

#4789. The average of five numbers is 27. If one number is excluded, the average becomes 25. Find the excluded number.

#4790. The average age of 35 students in a class is 16 years. The average age of 21 students is 14. What is the average age of remaining 14 students?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solutions #4789 and #4790 are correct. Keep it up!

#4791. The average score of a cricketer for 10 matches is 38.9 runs. If the average for the first six matches is 42, then find the average for the last four matches.

#4792. The average of six numbers is 3.95. The average of two of them is 3.4, while the average of the two is 3.85. What is the average of the remaining two numbers?

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi;

**In mathematics, you don't understand things. You just get used to them.**

Offline

**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 16,319

Hi bobbym,

The solution #4791 is perfect. Excellent!

I am sorry, I made an error in the question #4792.

The problem #4792 is to read

'The average of six numbers is 3.95. The average of two of them is 3.4, while the average of the other two is 3.85. What is the average of the remaining two numbers?'

'

Character is who you are when no one is looking.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 93,581

Hi ganesh;

**In mathematics, you don't understand things. You just get used to them.**

Offline