let's firstly convert the mixed fraction to improper fraction and then divide.
[tex]\bf \textit{how many times does }10\frac{1}{2}\textit{ go into }\frac{1}{4}?\qquad 10\frac{1}{2}\div \frac{1}{4} \\\\\\ \stackrel{mixed}{10\frac{1}{2}}\implies \cfrac{10\cdot 2+1}{2}\implies \stackrel{improper}{\cfrac{21}{2}} \\\\\\ \cfrac{21}{2}\div \cfrac{1}{4}\implies \cfrac{21}{2}\cdot \cfrac{4}{1}\implies \cfrac{21}{1}\cdot \cfrac{4}{2}\implies \cfrac{21}{1}\cdot 2\implies 42[/tex]
