If she stopped at 8;05, and she started 20 minutes earlier, just imaging a clock at 8:05 and turn back time 20 minutes.
Five minutes would be 8:00, ten minutes is 7:55, fifteen minutes is 7:50, and twenty minutes is 7:45. This, she started at 7:45
4.33
<span>4.1 × 10^13 / 9.46 × 10^12= 4.33</span>
It should be about 16.67% (or 17%) of it.
This cracker should be manufactured because the percent of people thinking the cracker tasted best is greater than the competitor's cracker. This means you will know that your cracker and it's quality is at least better than the two others.