Let X be a random sample representing the score of a student in the American Chemical Society Examination.
P(450 < x < 500) = P((450 - 500)/(90/sqrt(25)) < z < (500 - 500)/(90/sqrt(25))) = P(-2.778 < z < 0) = P(z < 0) - P(z < -2.778) = P(z < 0) - [1 - P(z < 2.778)] = P(z < 0) + P(z < 2.778) - 1 = 0.5 + 0.99727 - 1 = 0.49727 = 49.7%
<u>Question</u> : 8

<u>Question</u> : 9
<u>Question</u> : 11
<u>Question</u> : 12
Solution is in attachment ~
Given:
Angle A is 4 degrees greater than the measure of Angle B. Both angles are complementary
Complementary angles have a sum of 90°
Angle A = x + 4° ; Angle B = x
x + 4° + x = 90°
2x = 90° - 4°
2x = 86°
x = 86° ÷ 2
x = 43° ANGLE B.
Angle A = x + 4° ⇒ 43° + 4 = 47°
Given:
Angle D is 5 times the measure of Angle E. These angles are supplementary. This means that their sum is 180°
Angle D = 5x ; Angle E = x
5x + x = 180°
6x = 180°
x = 180° ÷ 6
x = 30° Angle E.
Angle D = 5x = 5(30) = 150°
Less than right? Because it’s a negative?