## College Algebra (6th Edition)

$=4.2\times10^{4}$
$$(1.4\times10^{15})(3\times10^{-11})$$ Regroup like terms then simplify $$=(1.4\times3)(10^{15}\times10^{-11})$$ $$=4.2\times10^{(15+(-11))}$$ $$=4.2\times10^{4}$$