Question

4000 key depressions per hour means how many words per minute

Answer 1

$as \: we \: know \: that \: \\ \\ 1hour \: = 60minutes \\ \\ according \: to \: given \: condition \: \\ \\ key \: depressions \: per \: minute \: = \\ \frac{4000}{60} \\ = \frac{400}{6} \\ = 66.66per \: minute \\ \\ \\ it \: will \: definetly \: help \: u.....$