Question 32548
{{{ ((0.00014)/(3.2*10^-12))) }}} * {{{ ((2.6*10^-12)/(3.9*10^12))) }}}
First ... change the numerator of the first fraction to scientific notation as well.
{{{ ((1.4*10^-4)/(3.2*10^-12))) }}} * {{{ ((2.6*10^-12)/(3.9*10^12))) }}}
I would multiply first, since dividing first will give you a nasty decimal on the second fraction.
{{{ ((1.4*10^-4)(2.6*10^-12))/((3.2*10^-12)(3.9*10^12)) }}}
Multiply the decimals
1.4 * 2.6 = 3.64
3.2 * 3.9 = 12.48
Add the exponents
-4 + -12 = -16
-12 + 12 = 0
{{{ (3.64*10^-16)/(12.48*10^0) }}}
adjust the decimal in the denominator
{{{ (3.64*10^-16)/(1.248*10^1) }}}
Divide
3.64 / 1.248 = 2.91666.....
Subtract the exponents
-16 - 1 = -17
I would round this answer
{{{ 2.917 * 10^-17 }}}