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When given a number in the form $A \\times 10^n$, we can think of $n$ as a number telling us how many places to move the decimal point.

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When $n$ is positive, we move the decimal point to the right side, for example:

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\$1.5 \\times 10^3 = 1500.0 \\text{ .} \$

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When $n$ is negative, we move the decimal point to the left side, for example:

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\$1.5 \\times 10^{-3} = 0.0015 \\text{ .} \$

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When $n = 0$, we do not move the decimal point:

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\$1.5 \\times 10^0 = 1.5 \\text{ .}\$

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#### a)

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In $\\var{A[0]} \\times 10^\\var{ran}$, $n = \\var{ran}$ and so we move the decimal point {ran} places to the right.

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\$\\var{A[0]} ⇒ \\var{precround((A[0] * 10^ran), 0)}\$

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#### b)

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In $\\var{A[1]} \\times 10^\\var{-ran + 4}$, $n = \\var{-ran +4}$ and so we move the decimal point {ran -4} places to the left.

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\$\\var{A[1]} ⇒ \\var{A[1]*10^(-ran+4)}\$

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Write the following in decimal form.

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$\\var{A[0]} \\times 10^\\var{ran} =$  [[0]]

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Given some numbers in standard index form, convert to decimal form.

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