We have been given that the standard deviation of a group of 20 scores is 15 and we are asked to find variance.
Since we know variance is square of standard deviation. In order to find out the variance of the given data we have to take the square of 15.
Therefore, our variance is 225.
The area of a parallelogram is equal to the base multiplied by the height. So in this instance it would be (3x+5)*(7x-1). Foil out the binomials. 21x^2+35x-3x-5 Combine like terms. 21x^2+32x-5
The area is 21x^2+32x-5
Answer:
1.72
Step-by-step explanation:
AB tangent at D, AD = OD = 4
so triangle OAD is right angle with side of 4 and 4.
area of OAD = 1/2 * 4 * 4 = 8
Angle AOD = DAO = 45 deg.
so circular sector OCD area = area of circle O * 45/360
= pi * 4 * 4 * 45/360
= 2pi
Shade area ACD = trigangle OAD - circular sector OCD
= 8 - 2pi
= 1.72
