μ = mean = 10.72 oz
σ =standard deviation = 0.14
x = 10.5
First, find the z-score:
z = x - μ / σ
z = (10.5 - 10.72) / 0.14 = -1.57143
Then find the value on the z-score table:
P (x < 10.5) = 0.058042
P(a or b)= p(a)+p(b)-p(a and b)
0.7=0.6+p(b)-0.3
p(b)=0.4
p(a or b)= p(a)+p(b)-p(a and b)
=0.6+0.4-0.3
=0.7
7√6 or in decimal form it’s 17.1464819....
Given
d(t) = 0.8t ^2
t= 5 secs
d(5) = 0.8(5)^2 = 0.8 * 25 = 20
t= 10 secs
d(10) = 0.8(10)^2 = 0.8 * 100 = 80
20 m / 5 secs = 4 meters per sec
80 m / 10 sec = 8 meters per sec
4 mps + 8 mps = 12 mps
12 mps / 2 = 6 mps
6 mps is the average speed of the rock between 5 and 10 sec after being dropped
