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Multiply two numbers in standard form, then divide two numbers in standard form.
", "licence": "Creative Commons Attribution 4.0 International"}, "statement": "Simplify, leaving the result in standard index form.
", "advice": "We use the rules for multiplying and dividing powers.
\nTo multiply powers we add, for example $10^2 \\times 10^6 = 10^{(2+6)} = 10^{8}$.
\nTo divide powers we subtract, for example $10^2 \\div 10^6 = 10^{(2-6)} = 10^{-4}$.
\n\n
\\[ \\begin{align} (\\var{int} \\times 10^\\var{ran - 3} ) \\times (\\var{int - 11} \\times 10^\\var{ran}) &= \\var{int} \\times (\\var{int-11}) \\times 10^{(\\var{ran - 3} + \\var{ran})} \\\\&= (\\var{int*(int-11)}) \\times 10^{\\var{ran - 3 + ran}} \\end{align} \\]
\nWe want to write this number in standard form so we move decimal place one place to the left to get
\n\\[(\\var{int*(int-11)/10}) \\times 10^{(\\var{ran - 3 + ran} + 1)} = (\\var{int*(int-11)/10}) \\times 10^{\\var{ran - 2 + ran}} \\text{.}\\]
\nSimilarly,
\n\\[ \\begin{align} (\\var{int*int} \\times 10^\\var{ran -4} ) \\div (\\var{int} \\times 10^\\var{ran - 2}) &= \\var{int*int} \\div \\var{int} \\times 10^{(\\var{ran - 4} - \\var{ran -2})} \\\\&= \\var{int} \\times 10^{-2} \\text{.}\\end{align} \\]
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", "licence": "Creative Commons Attribution 4.0 International"}, "type": "question", "advice": "The easiest way to do this is to convert these numbers in standard form into decimals, do the calculation with decimal forms, then change them back into standard form.
\n\\[\\begin{align} \\var{B[0]} \\times 10^3 + \\var{B[1]} \\times 10^4 &= \\var{B[0]*10^3} + \\var{B[1]*10^4} \\\\&= \\var{B[0]*10^3 + B[1]*10^4} \\\\&= \\var{(B[0]*10^3 + B[1]*10^4)/10^4} \\times 10^4\\end{align}\\]
\n\n
\\[\\begin{align} \\var{B[2]} \\times 10^3 - \\var{B[2] - 1.70} \\times 10^2 &= \\var{B[2]*10^3} - \\var{(B[2] - 1.70)*10^2} \\\\&= \\var{(B[2]*10^3) - ((B[2] - 1.70)*10^2)} \\\\&= \\var{(B[2]*10^3 - (B[2] - 1.70)*10^2)/10^3} \\times 10^3\\end{align}\\]
", "statement": "Calculate the following and write the result in standard index form (for example, for $2.01\\times 10^5$ we would write 2.01*10^5
in the gap).
$\\var{B[0]} \\times 10^3 + \\var{B[1]} \\times 10^4 =$ [[0]]
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