Assume that when adults with smartphones are randomly selected, 54% use them in meetings or classes. If 12 adult smartphone users are randomly selected, find the probability that fewer than 3 of them use their smartphones in meetings or classes. Round to 5 decimal places.

P(x < 3) = 0.0096

Step-by-step explanation:

We would assume a binomial distribution for the number of adults that use their smart phones in meetings or classes. The formula is expressed as

P(x = r) = nCr × p^r × q^(n - r)

Where

x represent the number of successes.

p represents the probability of success.

q = (1 - r) represents the probability of failure.

n represents the number of trials or sample.

From the information given,

p = 54% = 54/100 = 0.54

q = 1 - p = 1 - 0.54

q = 0.46

n = 12

P(x < 3) = P(x = 0) + P(x = 1) + P(x = 2)

Therefore,

P(x = 0) = 12C0 × 0.54^0 × 0.46^(12 - 0) = 0.0000897

P(x = 1) = 12C1 × 0.54^1 × 0.46^(12 - 1) = 0.0013

P(x = 2) = 12C2 × 0.54^2 × 0.46^(12 - 2) = 0.0082

Therefore,

P(x < 3) = 0.0000897 + 0.0013 + 0.0082 = 0.0096

0.6, 3/5, and 6% are the 3 same portion.

but, when they're all changed to a decimal they would equal to 0.6.

hope this , good luck!

2 & 7

step-by-step explanation:

he climbs 300 ft/hr at a constant rate. the peak is at 1,500 ft.

when going up, he reaches 600 ft in 2 hours. remember, that he is going in a constant rate. divide 600 with 300:

600/300 = 2

assuming that he takes the same route back (meaning that it's a 1500 ft route back, you can solve.

note also that you are solving when he gets back to 600 ft after he reaches the peak.

first, find the amount of hours it takes to get up the peak. divide the total amount (1500), with the ft/her (300) to get the amount of hours (x):

1500/300 = x

x = 5

it takes jamie 5 hours to get up. now, he is returning down, and reaches 600 (his current destination). remember that he climbs at a constant 300 ft/hr. divide 600 with 300:

600/300 = x

x = 2

now add the two numbers together.

x = 5 + 2 = 7

jamie takes 7 hours to go up the mountain and reach his current position when descending.

(total amount/constant rate) = (time).

remember that it is a constant rate, so in total, when he gets back down the mountain, it will take the same amount of time as when he goes up. the total amount for the round trip is: 5 + 5 = 10.

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