Question Number 165653 by mathlove last updated on 06/Feb/22
Commented by mr W last updated on 06/Feb/22
$${i}\:{thought}\:{all}\:{the}\:{time}\:{you}\:{guys}\:{are} \\ $$$${all}\:{no}\:{primary}\:{school}\:{pupils}\:{more}... \\ $$
Commented by mr W last updated on 06/Feb/22
$${the}\:{question}\:{seems}\:{to}\:{be}\:{the}\:{same} \\ $$$${as}\:{Q}\mathrm{165639}... \\ $$
Answered by alephzero last updated on 06/Feb/22
$$\frac{\mathrm{3}}{\mathrm{7}}\:−\:\mathrm{boys} \\ $$$$\mathrm{132}\:\mathrm{girls} \\ $$$$\Rightarrow\:\mathrm{1}\:−\:\frac{\mathrm{3}}{\mathrm{7}}\:=\:\frac{\mathrm{4}}{\mathrm{7}}\:−\:\mathrm{girls} \\ $$$$\Rightarrow\:\mathrm{132}\::\:\frac{\mathrm{4}}{\mathrm{7}}\:=\:\frac{\cancel{\mathrm{132}}\:\centerdot\:\mathrm{7}}{\cancel{\mathrm{4}}}\:=\:\mathrm{33}\:\centerdot\:\mathrm{7}\:=\: \\ $$$$=\:\mathrm{231}\:\mathrm{pupils}\:\mathrm{altogether} \\ $$