Question

Find the indicated area under the curve of the standard normalâ distribution; then convert it to a percentage and fill in the blank. Aboutâ ______% of the area is between zequals=minusâ1 and zequals=1 â(or within 1 standard deviation of theâ mean). About nothingâ% of the area is between zequals=minusâ1 and zequals=1 â(or within 1 standard deviation of theâ mean).

Answer 1

68.26%

Explanation:

The z score is a measure used in statistic to determine the number of standard deviations by which the raw score is above or below the mean. If the z score is positive then the raw score is above the mean and if it is negative then the raw score id below the mean. The z score is calculated using:

`z=(x-\mu)/(\sigma)\\ where\ \mu \ is \ the\ mean, \sigma\ is\ the\ standard\ deviation\ and\ x \ is\ the\ raw\ score`

From the normal distribution table, Area between z equal -1 and z equal 1 = P(-1 < z < 1) = P(z < 1) - P(z < -1) = 0.8413 - 0.1587 = 0.6826 = 68.26%

About 68.26% of the area is between z = -1 and z = 1 (or within 1 standard deviation of the mean).