John needs an average of 80 in English to make his parents happy. He now has an average of 78.5 based on four grades of 73, 84, 79, and 78. What grade does he need to get on his last
test to bring his average up to 80 ?

Acompany produces packets of soap powder labeled “giant size 32 ounces.” the actual weight of soap powder in such a box has a normal distribution with a mean of 33 oz and a standard deviation of 0.7 oz. to avoid having dissatisfied customers, the company says a box of soap is considered underweight if it weighs less than 32 oz. to avoid losing money, it labels the top 5% (the heaviest 5%) overweight. how heavy does a box have to be for it to be labeled overweight?