Answer:
<em>The observed t (2.533) is in the tail cut off by the critical t (2.462), therefore we reject H0. It is likely that the books are older than 20 years of age on average.</em>
Step-by-step explanation:
<em>Step 1: Hypotheses and α level
</em>
H0: μ ≤ 20
H1: μ > 20
<u><em>α = 0.01</em></u>
<em>Step 2: Critical region
</em>
α = .01
One-tailed
df = n – 1 = 30 – 1 = 29
<u><em>t - critical = 2.462
</em></u>
<em>Step 3: Calculate t which is observed
</em>
sM = √(s2 / n) = √(67.5 / 30) = 1.5
t = (M – μ) / sM
t = (23.8 – 20) / 1.5
<u><em>t = 2.533
</em></u>
<u><em /></u>
Which digit is underlined?
Answer:
She bought 7 shirts
88 kids were going on a field trip. Each car could hold 9 kids, and 25 kids decided to ride the bus. How many cars were needed?
Step-by-step explanation:
9x=63
x=7
Answer:
3a-12c
Step-by-step explanation:
(5a-7c)-(2a+5c)
5a-7c-2a-5c
(5a-2a)+(-7c-5c)
3a-12c
Step-by-step explanation:
- Given:ABCD is a rectangle, AC and BD intersect at O
- To prove: ∆ABC and ∆BAD are congruent.
- Proof: