Step-by-step explanation:
[tex]2 \frac{1}{3} crosswords= \frac{2}{5} hours[/tex]
[tex](2\frac{1}{3} ) \div 2 = \frac{1}{5} [/tex]
[tex]1 \frac{1}{6} = \frac{1}{5} [/tex]
[tex] \frac{1}{5} \times 5 = 1 \: hour[/tex]
therefore;
[tex]1 \frac{1}{6} \times 5 = 1 \: hour[tex]
which equals to 5 and 5 sixth crosswords per hour