Help multiple choice

A device produces random 64-bit integers at a rate of one billion per second. After how many years of running is it unavoidable

nikitadnepr [17]

Answer:

3171 × 10^(44) years

Step-by-step explanation:

For each bit, since we are looking how many years of running it is unavoidable that the device produces an output for the second time, the possible integers are from 0 to 9. This is 10 possible integers for each bit.

Thus, total number of possible 64 bit integers = 10^(64) integers

Now, we are told that the device produces random integers at a rate of one billion per second (10^(9) billion per second)

Let's calculate how many it can produce in a year.

1 year = 365 × 24 × 60 × 60 seconds = 31,536,000 seconds

Thus, per year it will produce;

(10^(9) billion per second) × 31,536,000 seconds = 3.1536 × 10^(16)

Thus;

Number of years of running is it unavoidable that the device produces an output for the second time is;

(10^(64))/(3.1536 × 10^(16)) = 3171 × 10^(44) years

6 0

3 years ago

Question 1

Alexxx [7]

Answer:

Water needed for pool = 486 cubic feet

Plastic liner required for the pool = 298.3 feet

Step-by-step explanation:

Top view of the pool is a composite figure, having one rectangle and a trapezoid.

1). Water needed for the pool = volume of the pool

Volume of the pool = Area of the base × Depth

= (Area of the rectangle + Area of the trapezoid)× depth

Area of the trapezoid = $\frac{1}{2}(b_{1}+b_{2})\times h$

= $\frac{1}{2}(11+9)\times (12-1.5)$

= 105 ft²

Area of the rectangle = Length × width

= 11 × 1.5

= 16.5 ft²

Now, volume of the pool = (105 + 16.5) × 4

= 121.5 × 4

= 486 cubic feet

b). Liner required = surface area of the pool excluding top

= Surface area of the walls + Area of the pool base

= (Perimeter of the pool) × depth + area of the base

= (12 + 11 + 1.5 + 10.7 + 9)×4 + 121.5

= 176.8 + 121.5

= 298.3 square feet

Therefore, amount of water required = 486 cubic feet

liner needed = 298.3 square feet

8 0

3 years ago

Records show that 12% of all college students are foreign students who also smoke. It is also known that 40% of all foreign coll

Sati [7]

Answer: the percent of the students at this university are foreign = 30%

Step-by-step explanation:

Given: Probability that college students are foreign students who also smoke: P(S|F)=0.12

Probability that foreign college students smoke P(S∩F)=0.4

The probability that the students at this university are foreign :

$P(F)=\dfrac{P(S\cap F)}{P(S|F)}$ [By conditional probability formula]

$=\dfrac{0.12}{0.4}\\\\=0.3$

Hence, the percent of the students at this university are foreign = 30%

6 0

3 years ago

A bag contains 7 pieces of paper numbered 1 to 7. P(2)=. Is

pochemuha

Answer:

$P (2) =\frac{1}{7}$ Theoretical probability

Step-by-step explanation:

The theoretical probability is defined as:

$P = \frac{number\ of\ desired\ results}{number\ of\ possible\ results}$

In this case we look for the probability of taking a 2 out of the bag. As there is only one paper with the number 2 in the bag then:

number of desired results = 1

The amount of paper in the bag is equal to 7, so:

number of possible results = 7

Thus:

$P (2) =\frac{1}{7}$

This is a theoretical probability, since we do not need to perform the experiment to calculate the probability.

To calculate the experimental probability we must perform the following experiment:

Take a paper out of the bag, record the number obtained and then return the paper to the bag.

Now repeat this experiment n times. (Perform n trials)

So:

$P (2) = \frac{number\ of\ times\ you\ obtained\ the\ number\ 2}{number\ of\ trials\ performed}$

To calculate a theoretical probability you always need to perform an experiment with n trials.

5 0

3 years ago

Please help! click to see the picture

Roman55 [17]

Answer:
Inequality 7n - 22 >= 64
Solution 7n > = 64 + 22
7n >= 86
n => 12. 28 rounded down to 12
Grace must wash at last 12 cars

4 0

3 years ago