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Question Number 130899 by greg_ed last updated on 30/Jan/21
$$\mathrm{There}\:\mathrm{are}\:\mathrm{20}\:\mathrm{persons}\:\mathrm{at}\:\mathrm{a}\:\mathrm{party}. \\ $$$$\mathrm{Maria}\:\mathrm{dansed}\:\mathrm{with}\:\mathrm{7}\:\mathrm{boys}, \\ $$$$\mathrm{Stacy}\:\mathrm{dansed}\:\mathrm{with}\:\mathrm{8}\:\mathrm{boys}, \\ $$$$\mathrm{Monia}\:\mathrm{dansed}\:\mathrm{with}\:\mathrm{9}\:\mathrm{boys}\:\mathrm{and} \\ $$$$\mathrm{Eve}\:\mathrm{dansed}\:\mathrm{with}\:\mathrm{all}\:\mathrm{the}\:\mathrm{boys}\:\mathrm{at}\:\mathrm{the}\:\mathrm{party}. \\ $$$$\boldsymbol{\mathrm{How}}\:\boldsymbol{\mathrm{many}}\:\boldsymbol{\mathrm{girls}}\:\boldsymbol{\mathrm{are}}\:\boldsymbol{\mathrm{there}}\:\boldsymbol{\mathrm{at}}\:\boldsymbol{\mathrm{the}}\:\boldsymbol{\mathrm{party}}\:? \\ $$
Commented by mr W last updated on 30/Jan/21
$${at}\:{least}\:\mathrm{4} \\ $$$${at}\:{most}\:\mathrm{11} \\ $$