If you divide a fraction over a number, you can just muplitply the denominator (the number under the line) by the number by which you divide:
[tex] \frac{99}{100*21} [/tex]
99 and 21 are divisible by 3, so we can divide them both by it:
[tex] \frac{33}{100*7} [/tex]
but that's all we can do!
so let's multiply
[tex] \frac{33}{700} [/tex]
and it's its simplest form
