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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

#7706. The average age of a husband and wife, who were born 7 years ago, was 25 years at the time of their marriage. Now, the average age of family, including husband, wife, and a child (born during the interval) is 22 years. What is the present age of the child?

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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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

#7707. There were 24 students in a class. One of them, who was 18 years old, left the class and his place was taken by a newcomer. If the average of the class was thereby lowered by 1 month, find the age of the newcomer.

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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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

#7708. 19 persons went to a hotel for a combined dinner party. 13 of them spent $79 each on their dinner and the rest spent $4 more than the average expenditure of all the 19. What is the total money spent by them (approximately)?

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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**math9maniac****Member**- From: Tema
- Registered: 2015-03-30
- Posts: 441

*Last edited by math9maniac (2020-02-14 05:31:40)*

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

Good attempt, math9maniac!

#7709. The average of five positive numbers is 213. The average of the first two numbers is 233.5 and the average of the last two numbers is 271. What is the third number?

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

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

#7710. If

then find the value ofNothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi,

#7711.27 pens are divided among Amy, Ursula, and Gia such that the ratio of pens with Amy and Ursula is 1:2 and that with Ursula and Gia is 4:3. How many pens did Amy get?

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

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#7712. A certain amount of money was divided between Sam and Ben in the ratio 2:3. If Sam's share is $2400, find Ben's share.

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**math9maniac****Member**- From: Tema
- Registered: 2015-03-30
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Only a friend tells you your face is dirty.

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**math9maniac****Member**- From: Tema
- Registered: 2015-03-30
- Posts: 441

ganesh wrote:

Hi,

Solution #7708

Good attempt, math9maniac!

Dear ganesh,

Thanks for sharing your solution. I think the answer can be 1536 if each of the remaining 6 spent 4 more than the average. Since, the question didn't indicate anything about each, I worked it as the combined 6/. The question stated "13 of them spent $79 each on their dinner and the rest spent $4 more than the average expenditure of all the 19." The 'each' clause was only stated for the 13, but 'the rest [6 pf them] spent $4 more than the ...

I would love your feedback on this. Many thanks

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

Hi math9maniac,

Your interpretation #7708 is beyond my comprehension.

Solution #7712 is correct. Neat work!

#7713. If 45% of a number is added to another number, the first number becomes 1.35 times of the other number. What is the ratio of these two numbers?

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**ganesh****Administrator**- Registered: 2005-06-28
- Posts: 29,750

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#7714. The first, second, and fourth term of a proportion are 3, 17, and 51. Find the third term.

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

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