How can I get decimal answers on my TI-89 calculator when using pi?

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To obtain decimal answers on a TI-89 calculator when using pi, users should check the calculator's mode settings to switch between decimal and exact formats. Inputting expressions like 2(pi)x1.0 can also yield decimal results. Pressing the green button with a dot allows toggling between exact and decimal answers, depending on the current mode. The calculator defaults to exact values to prevent rounding errors, which can be adjusted in the settings. Understanding these functionalities can help users effectively manage their calculations.
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This is not necessarily a math question, but I have a problem with a TI-89 calculator. Calculating something with pi doesn't give me a decimal answer. For example, if I put in 2*pi, it will just give an answer of 2pi instead of 6.28. How do I fix this?
 
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It frequently does that sort of thing, preferring things like 3/5, for example. Unfortunately I have been told not to just give away answers, so I can only say that you have to study the manual. One reason the calculator does that is to avoid the error of round off.

However, besides a certain button, just like with PARI--a free download--you can sometimes get around such things by writing 2(pi)x1.0, and trying that.
 
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Two solutions as far as I can remember. I think there is a setting in modes for decimal or exact and settings, you could switch that.

Or if you press the green button (the one with the dot) it will give answers in decimal if you are in exact mode, and exact answers if you are in decimal mode.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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