what are class intervals

A random sample of 86 days taken at a large hospital shows that an average of 32 patients were treated per day. The 95% confidence interval of the mean number of patients treated each day at the hospital is between 30 and 34. Find the 95% confidence interval of the mean number o..

The mean score on a standardized test is 100 with a standard deviation of 8. A random sample of 48 scores was found to have a mean of 98. Find the 95% confidence interval. => The interval is between 97.75 and 102.25 or The interval is between 1.15 and 100 or The i..

Using the stem-and-leaf plot, find the number of data items in the interval 20 - 49. => 10 or 6 or 9 or 12..

If a 100-foot lake's width is measured at 10-foot intervals (as shown), approximate the area of the lake using the Trapezoidal Rule. => 13100 ft 2 or 13120 ft 2 or 13200 ft 2 or None of the above..

Approximate the area of the region below the graph over the interval [1, 7] by using RRAM. [Use 12 rectangles.] => 23 square units or 40 square units or 25 square units or 29.25 square units..

Find the area under the curve from the given graph over the interval [1, 4] by using PRAM. [Use 6 rectangles.] => 26.9858 square units or 36.9 square units or 38 square units or 30 square units..

Approximate the area of the region below the graph over the interval [0, 2] by using PRAM.[Use 8 rectangles.] => 4.0125 cm 2 or 1.0125 cm 2 or 2.0125 cm 2 or 3.0125 cm 2..

The number of vehicles that crossed at a traffic junction per minute at different intervals are: 120, 138, 127, 135, 132, 124, 130, 134. Find the mean and variance. => Mean = 138; Variance = 31.7 or Mean = 130; Variance = 22.3 or Mean = 130; Variance = 31.7 or Mean = 138; Variance = 30.7 ..

A sample of 300 tickets purchased during vacation at a travelling center included 45 children's tickets. Find the 95% confidence interval for the true proportion of children, who were traveling during the vacation. => 11% < p <19% or 13% < p <17% or 12.9% < p <17.1% or 1..

In a survey of 407 students, 270 indicated that they use a computer at least once a day. Find the 95% confidence interval for the true proportion of students who use computer at least once a day. => 0.614 < p < 0.706 or 0.418 < p < 0.902 or 0.294 < p < 0.386 or 0.637 <..