Suppose that 50 identical batteries are being tested. after 8 hours of continuous use, assume that a given battery is still operating with a probability of 0.70 and has failed with a probability of 0.30. what is the probability that between 25 and 30 batteries (inclusive) will last at least 8 hours

Liz had 140 pens and inna had 100 pens. after inna gave liz some pens, liz had 3 times as many pens as inna. how many pens did inna give liz?

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.

Amanda went into the grocery business starting with five stores. after one year, she opened two more stores. after two years, she opened two more stores than the previous year. if amanda expands her grocery business following the same pattern, which of the following graphs represents the number of stores she will own over time?