1 - 2x < 11
-2x < 10
x < -5
Jack's mistake is that he was supposed to divide by -2 on both sides of the inequality, but he did not do that. By dividing by -2, he will get x < -5.
10 razors......1 lasts for 1 week...so 10 would last for 10 weeks.
1 week = 7 days...so 10 weeks = 70 days.
6.30 / 70 = 0.09 per day (it would cost 9 cents per day)
Jenny missed 7 problems on the 120 point test
