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# Geometry/Math

Question
I hope you can help I do not know if I am in the right place?

I am going to School to be an Electronic Tech.

And I have a Math formula I do not understand.

20,000 Divided by 300 and I get 66.66666
But I should get 66.67

Is this because the Second 6 after the Point is Higher then a 5 so I make it a 7 ?
Thanks.

If 20,000 is divided by 300, that is the same as 200 divided by 3 (dropping 00 from each).
If is known the 200/3 = 66 2/3.  In decimals, that is 66.66666666666666...

Since 6 round up, cutting it off at some point would give
66.667 to the nearest 1000th, 66.67 to the nearest hundredth, 66.7 to the nearest tenth,
67 to the nearest integer, and 70 when going to the nearest 10.

All you've got to remember is 5 is the key point.
Anything above 5 rounds to 10 and anything below 5 rounds to 0.

This means when rounding to 10ths, 0.41, 0.42, 0.43 and 0.44 would all round to 0.4 and
0.46, 0.47, 0.48, and 0.49 would all round to 0.5.  That means then 0.7500000000001 rounds to 0.8 and 0.7499999999999 rounds to 0.7.

There is some discrepancy about which way 0.5 rounds.
Some say to always round 0.5 up, some say to always round 0.5 down,
but I believe in the more accurate version (in most cases) which says
to always round to the nearest even.

That is, when rounding to integer, 0.5 rounds to 0,
1.5 and 2.5 both round to 2,
3.5 and 4.5 both round to 4,
5.5 and 6.5 both round to 6,
7.5 and 8.5 both round to 8,
and 9.5 rounds to 10.

Geometry

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