Express the missing divisor using power of 10 5.2 divided by ------- = 0.052

If a fair coin is flipped 15 times, what is the probability that there are more heads than tails?

ludmilkaskok [199]

Answer:

The probability that there are more heads than tails is equal to $\dfrac{1}{2}$ .

Step-by-step explanation:

Since the number of flips is an odd number, there can't be an equal number of heads and tails. In other words, there are either

more tails than heads, or,
more heads than tails.

Let the event that there are more heads than tails be $A$ . $\lnot A$ (i.e., not A) denotes that there are more tails than heads. Either one of these two cases must happen. As a result, $P(A) + P(\lnot A) = 1$ .

Additionally, since this coin is fair, the probability of getting a head is equal to the probability of getting a tail on each toss. That implies that (for example)

the probability of getting 7 heads out of 15 tosses will be the same as
the probability of getting 7 tails out of 15 tosses.

Due to this symmetry,

the probability of getting more heads than tails (A is true) is equal to
the probability of getting more tails than heads (A is not true.)

In other words $P(A) = P(\lnot A)$ .

Combining the two equations:

$\left\{\begin{aligned}&P(A) + P(\lnot A) = 1 \cr &P(A) = P(\lnot A)\end{aligned}\right.$ ,

$P(A) = P(\lnot A) = \dfrac{1}{2}$ .

In other words, the probability that there are more heads than tails is equal to $\dfrac{1}{2}$ .

This conclusion can be verified using the cumulative probability function for binomial distributions with $\dfrac{1}{2}$ as the probability of success.

$\begin{aligned}P(A) =& P(n \ge 8) \cr =& \sum \limits_{i = 8}^{15} {15 \choose i} (0.5)^{i} (0.5)^{15 - i}\cr =& \sum \limits_{i = 8}^{15} {15 \choose i} (0.5)^{15}\cr =& (0.5)^{15} \left({15 \choose 8} + {15 \choose 9} + \cdots + {15 \choose 15}\right) \cr =& (0.5)^{15} \left({15 \choose (15 - 8)} + {15 \choose (15 - 9)} + \cdots + {15 \choose (15 - 15)} \right) \cr =& (0.5)^{15} \left({15 \choose 7} + {15 \choose 6} + \cdots + {15 \choose 0}\right)\end{aligned}$

$\begin{aligned}\phantom{P(A)} =& \sum \limits_{i = 0}^{7} {15 \choose i} (0.5)^{15}\cr =& P(n \le 7) \cr =& P(\lnot A)\end{aligned}$ .

6 0

4 years ago

A restaurant manager states the number of customers that enter the restaurant is equal to 3 times the number of people that buy

kotegsom [21]

The answer to this question will be 45 because you minus 15 on both sides and get 45 for 60 minus 15 and then will minus 2x on both sides and the Equation will now be x=45 and you plug it in to check

8 0

3 years ago

A cafeteria measures 40 feet by 60 feet.

Mariulka [41]

B, feet squared.
This is because we are finding the area of a square, not a cube.

3 0

3 years ago

Read 2 more answers

What percent of 50 is 10

gayaneshka [121]

50% of 10 is just half so half of 10 is 5
The answer is five

5 0

3 years ago

Read 2 more answers

HEY YOU!! PLEASE I NEED HELPPP<br><br> find angle BAC and angle FAB

serious [3.7K]

Answer:

m∠BAC = 105°

m∠FAB = 75°

Step-by-step explanation:

By using the property of an exterior angle of a triangle,

Measure of an exterior angle is equal to the sum of opposite two angles of a triangle.

From the triangle given in the picture,

m∠ABC + m∠BCA + m∠CAB = 180°

(13x - 3)° = (3x + 2)° + 55°

13x - 3 = 3x + 57

13x - 3x = 57 + 3

10x = 60

x = 6

m∠FAB = (13x - 3)° = 75°

m∠ABC = (3x + 2)° = 20°

Since, ∠BAC and ∠FAB are the linear pair of angles,

m∠BAC + m∠FAB = 180°

m∠BAC + 75° = 180°

m∠BAC = 180° - 75° = 105°

8 0

3 years ago