The y has to be negative but the x positive. So that leaves only (3,-4)
Assuming a normal distribution we find the standardized z scores for a:-
z1 = (80 - 180) / 25 = = -100/25 = -4
z2 = (280-180) / 25 = 4
Required P( -4 < z < 4) from the tables is >99.9%
b
z1 = 130-180 / 25 = -2
z2 = 230-180 / 25 = 2
from tables probability is 2* 0.4773 = 95.46 %
It would be rounded down to 244 as its only .1 so its closer to 244 than it is to 245
We can solve for the arc length using the formula shown below:
Arc Lenght = 2pi*r(central angle/360)
We need to convert the central angle such as:
Central angle = 23pi rad * (180°/pi rad) = 23*180
Radius = 24cm
Solving for arc length:
Arc length = 2*3.14 *24*(23*180/360)
Arc length = 1733.28 cm
