Answer:
m<FED=60, m<DEN=120
Step-by-step explanation:
m<FED=60
This is because <GEN and <FED are vertical angles.
Vertical angles are always congruent.
Vertical angles are formed by a pair of intersecting lines, and are the angles directly across from one another.
m<DEN=120
This is because <DEN and <GEN are supplementary.
Supplementary angles add up to 180 degrees.
We know this because a straight line is always 180 degrees.
So:
m<DEN+m<GEN=180
m<DEN+60=180
m<DEN=120
Answer:
The Two Column Proof is given below.
Step-by-step explanation:
Given:
To Prove:
∠ P ≅ ∠ N
Proof:
In Δ MPO and Δ MNO
STATEMENT REASONS
1. MP ≅ MN 1. Given
2. PO ≅ NO 2. Given
3. MO ≅ MO 3. Reflexive property
4. ΔMPO ≅ ΔMNO 4. Side-Side-Side congruence test}
5. ∠MPO ≅∠MNO 5. Corresponding parts of congruent Triangles
i.e ∠ P ≅ ∠ N ..................Proved
Let's call our estimate x. It will be the average of n IQ scores. Our average won't usually exactly equal the mean 97. But if we repeated averages over different sets of tests, the mean of our estimate the average would be the same as the mean of a single test,
μ = 97
Variances add, so the standard deviations add in quadrature, like the Pythagorean Theorem in n dimensions. This means the standard deviation of the average x is
σ = 17/√n
We want to be 95% certain
97 - 5 ≤ x ≤ 97 + 5
By the 68-95-99.7 rule, 95% certain means within two standard deviations. That means we're 95% sure that
μ - 2σ ≤ x ≤ μ + 2σ
Comparing to what we want, that's means we have to solve
2σ = 5
2 (17/√n) = 5
√n = 2 (17/5)
n = (34/5)² = 46.24
We better round up.
Answer: We need a sample size of 47 to be 95% certain of being within 5 points of the mean
