Find the missing probability.<br> P(A) = ?<br> P(B) = 2/5<br> P(A and B) = 6/25

The number of gift baskets Nikki can make varies directly with the amount of time she spends making the baskets . She can make 1

scoundrel [369]

Answer:

40

Step-by-step explanation:

The number of gift baskets Nikki can make varies directly with the amount of time she spends making the baskets .

Let n be the number of baskets and let t be the mount of time it takes to make the basket. This means that:

n α t

=> n = kt

where k = constant of proportionality

She can make 4 baskets in every 1/2 hour.

This means that:

4 = k * 1/2

=> k = 4 * 2 = 8 baskets per hour

The time is now 5 hours (t = 5). Therefore:

n = 8 * 5 = 40 baskets

She can make 40 baskets in 5 hours.

8 0

3 years ago

How many sets of three consecutive integers are there in which the sum of the three integers equals their product?

skad [1K]

Answer:

3

Step-by-step explanation:

since the 3 integers are consecutive, we are dealing with x, x+1, x+2.

and their sum is the same as their product :

x + (x + 1) + (x + 2) = x(x + 1)(x + 2)

3x + 3 = x(x² + 3x + 2) = x³ + 3x² + 2x

x³ + 3x² - x - 3 = 0

this is a polynomial of third degree.

and as such it has 3 solutions.

of course, it could be that some of them are the same or are even in the realm of complex numbers (i = sqrt(-1)), but usually these 3 solutions are different real numbers.

I tried x=1 just to see, and, hey, it is a solution for this equation.

x = 1 means that the other 2 consecutive integers are 2 and 3.

and indeed, 1+2+3 = 1×2×3 = 6.

now it is easier to find the other 2 solutions, as a zero solution can be expressed as a factor of the whole expression.

for x = 1 the factor term is (x - 1), as this term is then turning 0, when x = 1.

I can divide the main expression by this factor and then analyze the quotient about the other 2 solutions.

x³ + 3x² - x - 3 : x - 1 = x² + 4x + 3

- x³ - x²

----------------

0 4x² - x

- 4x² - 4x

-----------------------

0 + 3x - 3

- 3x - 3

---------------------------

0 0

so, the original expression can be written as

(x² + 4x + 3)(x - 1).

now we need to find the 2 zero solutions for x²+4x+3

the general solution to a quadratic equation is

x = (-b ± sqrt(b² - 4ac))/(2a)

in our case

a = 1

b = 4

c = 3

so,

x = (-4 ± sqrt(4² - 4×1×3))/(2×1) =

= (-4 ± sqrt(16 - 12))/2 = (-4 ± sqrt(4))/2 =

= (-4 ± 2)/2 = -2 ± 1

x1 = -2 + 1 = -1

x2 = -2 - 1 = -3

so, we have the additional solutions :

-1 0 1

-3 -2 -1

-1 + 0 + 1 = -1×0×1 = 0

-3 + -2 + -1 = -3×-2×-1 = -6

and there we have it fully proven :

there are 3 different sets of 3 consecutive integers with the same sum as product.

4 0

2 years ago

the distribution of heights of adult American men is approximately normal with mean 68 in and a standard deviation of 2.5 in wha

melamori03 [73]

Let x be a random variable representing the heights of adult American men. Since it is normally distributed and the population mean and standard deviation are known, we would apply the formula,

z = (x - mean)/Standard deviation

From the information given,

mean = 68

standard deviation = 2.5

The probability that the height of a selected adult is between 63 and 73 is expressed as

$P(68\leq x\leq73)$

For x = 63,

z = (63 - 68)/2.5 = -2

Looking at the normal distribution table, the probability corresponding to the z score is 0.02275

For x = 73,

z = (73 - 68)/2.5 = 2

Looking at the normal distribution table, the probability corresponding to the z score is 0.97725

Therefore,

$P(68\text{ }\leq x\leq73)\text{ = 0.97725 - 0.0}2275\text{ = 0}.9545$

Thus, the percentage of men are between 63 and 73 is

0.9545 * 100 = 95.45%

Rounding up to the nearest percentage, the answer is 95%

8 0

1 year ago

Use the principle of inclusion and exclusion to find the number of positive integers less than 1,000,000 that are not divisable

wel

This is a simple problem based on combinatorics which can be easily tackled by using inclusion-exclusion principle.
We are asked to find number of positive integers less than 1,000,000 that are not divisible by 6 or 4.
let n be the number of positive integers.
∴ 1≤n≤999,999
Let c₁ be the set of numbers divisible by 6 and c₂ be the set of numbers divisible by 4.
Let N(c₁) be the number of elements in set c₁ and N(c₂) be the number of elements in set c₂.

∴N(c₁) = $\frac{999,999}{6} = 166666$
N(c₂) = $\frac{999,999}{4} = 250000$
∴N(c₁c₂) = $\frac{999,999}{24} = 41667$
∴ Number of positive integers that are not divisible by 4 or 6,

N(c₁`c₂`) = 999,999 - (166666+250000) + 41667 = 625000
Therefore, 625000 integers are not divisible by 6 or 4

8 0

3 years ago

(Can someone help me please?)

Scorpion4ik [409]

Answer:

10

Step-by-step explanation:

The answer is 10 because there are 20 days and no home work is due on 7 of those days so that’s 13 days with homework from math or writing. Then you take the three days where it was just math and subtract that to get 10 days of writing.

6 0

3 years ago

Find the missing probability. P(A) = ? P(B) = 2/5 P(A and B) = 6/25