# How do you write 2.45 times 10^5 times 3.2 times 10^7 in scientific notation?

$7.84 \times {10}^{12}$
rewriting the expression as : $2.45 \times 3.2 \times {10}^{5} \times {10}^{7}$
(using :  a^m xxa^n = a^(m+ n))
becomes : 7.84 $\times {10}^{12}$