You may have used the expression $\displaystyle\frac{{3}}{{5}}\div{42}\usepackage{cmbright}\Huge\$ . This would show how many groups of 42 there are in $\displaystyle\frac{{3}}{{5}}\usepackage{cmbright}\Huge\$ . You need to find how many $\displaystyle\frac{{3}}{{5}}\usepackage{cmbright}\Huge\$ are in 42, which is $\displaystyle{42}\div\frac{{3}}{{5}}\usepackage{cmbright}\Huge\$ . The correct answer is 70.