So that if pi stays x 2 then the perimeter will still be 3 x as big as the smaller circle. Which means it takes 3 full turns as to turn around the perimeter.

7 0

4 years ago

An unfair coin has a probability of coming up heads of 0.65. The coin is flipped 50 times. What is the probability it will come

Lady bird [3.3K]

Answer: the probability it will come up heads 25 or fewer times is 0.019

Step-by-step explanation:

Given that;

n = 50

p = 0.65

so, q = 1 - p = 0.35

np = 50 × 0.65 = 32.5 ≥ 10

nq = 50 × 0.35 = 17.5 ≥ 10

so, we need to use Normal Approximation for the Binomial Distribution

μ = np = 50 × 0.65 = 32.5

σ = √(npq) = √( 50 × 0.65 × 0.35 ) = 3.3726

now, the probability that it will come up heads 25 or few times will be;

⇒ P( x≤25)

{using continuity correction}

⇒ P[ z < (25.5 - 32.5)/3.3726 ]

⇒ P[ z < -2.0755 ]

using z-table

= 0.01923 ≈ 0.019 { 3 decimal places}

Therefore the probability it will come up heads 25 or fewer times is 0.019

4 0

3 years ago