The grade point average in an econometrics examination was normally distributed with a mean of 75. in a sample of 10 percent of students it was found that the grade point average was greater than 80. can you tell what the standard deviation of the grade point average was?

3 ft

step-by-step explanation:

since the triangle is right use pythagoras' identity to solve for a

the square on the hypotenuse is equal to the sum of the squares on the other two sides, that is

a² + 8² = ( )²

a² + 64 = 73 ( subtract 64 from both sides )

a² = 9 ( take the square root of both sides )

a = = 3

7 ft 6 in means 7 1/2, because 6 in is 1/2 of a foot. 7 ft 8 in means 7 2/3 because 8 in is 2/3 of a foot. 23/3 = 7 2/3. 15/2 = 7 1/2.

23/3   *   15/2   = 57 1/2

step-by-step explanation: