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Numbers/Rounding and estimating

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Notice: Incomplete

Estimating

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Rounding

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There are two main types of rounding, directed rounding and rounding to the nearest integer.

Directed Rounding

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Directed rounding is when one rounds all numbers in the same direction. There are four types, rounding up, rounding down, rounding towards zero and rounding away from zero.

Rounding Up

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To round up, you round all numbers to the integer after it.

Examples:

-1.7 rounds to -1

-1.3 rounds to -1

1.3 rounds to 2

1.7 rounds to 2

Rounding Down

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To round down, you round all numbers to the integer before it.

Examples:

-1.7 rounds to -2

-1.3 rounds to -2

1.3 rounds to 1

1.7 rounds to 1

Rounding Towards Zero

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To round towards zero, you round all numbers to the nearest integer that is closer to zero.

Examples:

-1.7 rounds to -1

-1.3 rounds to -1

1.3 rounds to 1

1.7 rounds to 1

Rounding Away From Zero

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To round away from zero, you round all numbers to the nearest integer that is further from zero.

Examples:

-1.7 rounds to -2

-1.3 rounds to -2

1.3 rounds to 2

1.7 rounds to 2

Rounding To the Nearest Integer

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Rounding to the nearest integer is self-explanatory. The problem is that some numbers don't have a 'nearest integer', notably, the numbers that are halfway between integers.