Answer: b) 84
Step-by-step explanation:
Let p be the prior estimate of the required proportion.
As per given , we have
p =0.5 (The probability of getting heads on a fair coin is 0.5)
Significance level : 
Critical z-value (using z-value table ) : 
Confidence interval width : w= 0.18
Thus , the margin of error : 
Formula to find the sample size ( if prior estimate of proportion is known.):-
Substitute the values , we get
Simplify ,
[Round of to the next whole number.]
Hence, the number of times we would have to flip the coin =<u>84</u>
hence, the correct answer is b) 84
Answer:
3(a - b)(a + b)
Step-by-step explanation:
Factorize: (2a - b)² - (a - 2b)²
- Different of Perfect a Square rule: a² - b² = (a + b)(a - b)
(2a - b)² - (a - 2b)² = [(2a - b) + (a - 2b)] × [(2a - b) - (a - 2b)]
1. Distribute and Simplify:
Distribute the (+) sign on the first bracket and simplify: [(2a - b) + (a - 2b)] → 2a - b + a - 2b → (3a - 3b)
Distribute the (-) sign on the first bracket and simplify: [(2a - b) - (a - 2b)] → 2a - b – a + 2b → (a + b)
We now have:
(3a - 3b)(a + b)
2. Factor out the Greatest Common Factor (3) from 3a - 3b:
(3a - 3b) → 3(a - b)
3. Add "(a + b)" back into your factored expression:
3(a - b)(a + b)
Hope this helps!
Answer:
The two numbers are:
30 and 18
Step-by-step explanation:
a + b = 48
a - b = 12
From the first eq.
a = 48 - b
Replacing this last value in the second eq.
(48 - b) - b = 12
48 - 2b = 12
48 - 12 = 2b
36 = 2b
36/2 = b
18 = b
from the first eq.
a + 18 = 48
a = 48 - 18
a = 30
Check:
from the second eq.
a - b = 12
30 - 18 = 12
Answer:
Step-by-step explanation:
hope this helps
Answer:
OF
Step-by-step explanation:
Since the arcs are congruent, the lines intercepting them are congruent, and you will get 2 congruent right triangles. So OA is congruent to OF by CPCTC.
