Ratio (Pri5)/ Ratio Huamin Primary School / Homework (2018) $\mathrm{Dave}\mathrm{and}\mathrm{Stan}\mathrm{were}\mathrm{selling}\mathrm{bags}\mathrm{at}\$19\mathrm{each}\mathrm{and}\$9\mathrm{each}\mathrm{respectively}.\phantom{\rule{0ex}{0ex}}\mathrm{Total}\mathrm{sales}\mathrm{collected}\mathrm{by}\mathrm{both}\mathrm{was}\$3976.\phantom{\rule{0ex}{0ex}}\mathrm{The}\mathrm{ratio}\mathrm{of}\mathrm{the}\mathrm{number}\mathrm{of}\mathrm{bags}\mathrm{sold}\mathrm{my}\mathrm{Dave}\mathrm{to}\mathrm{those}\mathrm{sold}\mathrm{by}\mathrm{Stan}\mathrm{is}7:1.\phantom{\rule{0ex}{0ex}}\mathrm{How}\mathrm{many}\mathrm{bags}\mathrm{did}\mathrm{Dave}\mathrm{sell}?$

$U=\mathrm{the}\mathrm{units}\mathrm{in}\mathrm{ratio}\phantom{\rule{0ex}{0ex}}D:S\phantom{\rule{0ex}{0ex}}7:1\phantom{\rule{0ex}{0ex}}7U(19)+U(9)=3976\phantom{\rule{0ex}{0ex}}133U+9U=3976\phantom{\rule{0ex}{0ex}}U=3976\xf7142=28\phantom{\rule{0ex}{0ex}}\phantom{\rule{0ex}{0ex}}\mathrm{Dave}\mathrm{sold}=7U\phantom{\rule{0ex}{0ex}}=7(28)\phantom{\rule{0ex}{0ex}}=196\mathrm{bags}\left(\mathrm{ans}\right)$ 


