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#1 2024-05-17 03:44:55
- mathxyz
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- From: Brooklyn, NY
- Registered: 2024-02-24
- Posts: 1,053
Sometimes pi, or 3.14 or 22/7
I come across questions that specifically ask for pi or 3.14 or 22/7 to be used for calculations. Why is that the case? For example, some questions say the following:
LEAVE YOUR ANSWER IN TERMS OF PI.
Why?
More math problems coming in the next 60 minutes.
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#2 2024-05-17 05:30:13
- Bob
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- Registered: 2010-06-20
- Posts: 10,627
Re: Sometimes pi, or 3.14 or 22/7
In any question involving a calculation with pi in it, you'd have to use a rounded value because pi has an infinite number of decimal places and it would take you forever. 
22/7 is a good approximation and I'd use it if the radius was a multiple of 7. The working would be a lot easier.
The only time you can avoid any approximation is if the pi value cancels out or they say leave the answer as a multiple of pi.
Such a question would suggest to me it's the method that is important, not the numeric answer.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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#3 2024-05-17 09:56:25
- mathxyz
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- From: Brooklyn, NY
- Registered: 2024-02-24
- Posts: 1,053
Re: Sometimes pi, or 3.14 or 22/7
In any question involving a calculation with pi in it, you'd have to use a rounded value because pi has an infinite number of decimal places and it would take you forever.
22/7 is a good approximation and I'd use it if the radius was a multiple of 7. The working would be a lot easier.
The only time you can avoid any approximation is if the pi value cancels out or they say leave the answer as a multiple of pi.
Such a question would suggest to me it's the method that is important, not the numeric answer.
Bob
Very good reply. Thanks.
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