High Water Content Fruits. Watermelon and strawberries contain about 92 percent water per volume. Other fruits with high water content include grapefruit with 91 percent, cantaloupe with 90 percent and peaches with 88 percent water. Fruits containing 87 percent water by weight include pineapple, cranberries, orange and raspberries.
The sample variance sÂ² is the best point estimate (or single value estimate) of the population variance ÏÂ². The sample standard deviation s is commonly used as a point estimate of Ï ( even though it is a biased estimator). (Sec 6-4 showed that sÂ² is an unbiased estimator of ÏÂ², but s is a biased estimator of Ï.)
This sample difference between the female mean of 5.35 and the male mean of 3.88 is 1.47. However, the gender difference in this particular sample is not very important. What is important is whether there is a difference in the population means. In order to test whether there is a difference between population means, we are going to make three assumptions: The two populations have the same variance. This assumption is called the assumption of homogeneity of variance.