Answer:
Option (C)
Step-by-step explanation:
In the given circle, AB is a chord passing through the center O.
Therefore,chord AB is a diameter of the circle and OC is the radius.
AO = OB = OC
OC⊥AB, and length of OC = 7 cm
By applying Pythagoras theorem in right ΔBOC,
BC² = OC² + OB²
BC = 
= 
=
≈ 9.9 units
Therefore, Option (C) will be the answer.
Answer:
A function
Step-by-step explanation:
The question is needed, but with the statement it can be determined that this situation would be, if a relationship or function, or given the case of both or neither.
Let's first define what a relationship is, define that a single input can have more than one output, applied to the statement would be that if you apply the same force in two different situations, the amount of candy that comes out may be different.
On the contrary, in a function for each input there is an output, a possible result, which is what they tell us in the statement.
Therefore this situation is represented by a function.
What is the question you are asking and no one is gonna know what lesson 3.2 means.
The question is incomplete! Complete question along with answer and step by step explanation is provided below.
Question:
The lifetime (in hours) of a 60-watt light bulb is a random variable that has a Normal distribution with σ = 30 hours. A random sample of 25 bulbs put on test produced a sample mean lifetime of = 1038 hours.
If in the study of the lifetime of 60-watt light bulbs it was desired to have a margin of error no larger than 6 hours with 99% confidence, how many randomly selected 60-watt light bulbs should be tested to achieve this result?
Given Information:
standard deviation = σ = 30 hours
confidence level = 99%
Margin of error = 6 hours
Required Information:
sample size = n = ?
Answer:
sample size = n ≈ 165
Step-by-step explanation:
We know that margin of error is given by
Margin of error = z*(σ/√n)
Where z is the corresponding confidence level score, σ is the standard deviation and n is the sample size
√n = z*σ/Margin of error
squaring both sides
n = (z*σ/Margin of error)²
For 99% confidence level the z-score is 2.576
n = (2.576*30/6)²
n = 164.73
since number of bulbs cannot be in fraction so rounding off yields
n ≈ 165
Therefore, a sample size of 165 bulbs is needed to ensure a margin of error not greater than 6 hours.