Question

When multiplying numbers in scientific notation you blank the coefficients and substract the exponents?

Answer 1

For the sake of example, let's multiply the two numbers $2.3 \times 10^5$ and $3.5 \times 10^7$ together. Altogether, we have:

$2.3\times10^5\times3.5\times10^7$

Rearranging the expression, we can group the exponents and coefficients together:

$2.3\times3.5\times10^5\times10^7$

Multiplying each out, we notice that since $10^5$ and $10^7$ have the same base (10), multiplying them has the effect of adding their exponents, which leaves us with:

$2.3\times3.5\times10^{5+7}=8.05\times10^{12}$

The takeaway here is that multiplying two numbers in scientific notation together has the effect of multiplying its coefficients and adding its exponents.