Answer
(a) $10^{6}~lb$
(b) $10^{4}~lb$
Work Step by Step
(a) $quarter=0.25~USD$
$12~millions~USD=(1.2\times10^{7}~USD)(\frac{1~quarter}{0.25~USD})\approx10^{8}~quaters$
The weight of a quarter is about $0.01~lb=10^{-2}~lb$
$Total~weight=(10^{8}~quaters)(\frac{10^{-2}~lb}{1~quarter})=10^{6}~lb$
(b) The weight of a dollar bill is about $0.001~lb=10^{-3}~lb$. $12~millions~USD\approx10^{7}~USD$
$Total~weight=(10^{7}~USD)(\frac{10^{-3}~lb}{1~USD})=10^{4}~lb$
