-20=x/3-8 I have no idea how to do this

The running time for movie a is 40 minutes more than twice the running time for movie

PtichkaEL [24]

3b - a = 45
a = 2b + 40

Solve simultaneously.

3b - (2b + 40) = 45
3b - 2b - 40 = 45
b = 45 + 40
b = 95min (1 hour 35 min)

a = 2 (95) + 40
a = 230min ( 3 hour 50 min)

4 0

3 years ago

A box contains 24 transistors,4 of which are defective. If 4 are sold at random,find the following probabilities. i. Exactly 2 a

zavuch27 [327]

SOLUTION

This is a binomial probability. For i, we will apply the Binomial probability formula

i. Exactly 2 are defective

Using the formula, we have

$\begin{gathered} P_x=^nC_x\left(p^x\right?\left(q^{n-x}\right) \\ Where\text{ } \\ P_x=binomial\text{ probability} \\ x=number\text{ of times for a specific outcome with n trials =2} \\ p=\text{ probability of success = }\frac{4}{24}=\frac{1}{6} \\ q=probability\text{ of failure =1-}\frac{1}{6}=\frac{5}{6} \\ ^nC_x=\text{ number of combinations = }^4C_2 \\ n=\text{ number of trials = 4} \end{gathered}$

Note that I made the probability of being defective as the probability of success = p

and probability of none defective as probability of failure = q

Exactly 2 are defective becomes the binomial probability

$\begin{gathered} P_x=^4C_2\times\lparen\frac{1}{6})^2\times\lparen\frac{5}{6})^{4-2} \\ P_x=6\times\frac{1}{36}\times\frac{25}{36} \\ P_x=\frac{25}{216} \\ =0.1157 \end{gathered}$

Hence the answer is 0.1157

(ii) None is defective becomes

$\begin{gathered} \lparen\frac{5}{6})^4=\frac{625}{1296} \\ =0.4823 \end{gathered}$

hence the answer is 0.4823

(iii) All are defective

$\begin{gathered} \lparen\frac{1}{6})^4=\frac{1}{1296} \\ =0.00077 \end{gathered}$

(iv) At least one is defective

This is 1 - probability that none is defective

$\begin{gathered} 1-\lparen\frac{5}{6})^4 \\ =1-\frac{625}{1296} \\ =\frac{671}{1296} \\ =0.5177 \end{gathered}$

Hence the answer is 0.5177

3 0

1 year ago

Sandra waits tables at Polly's Tamales. While she is working, she receives a discount on any food she buys. If an item normally

Musya8 [376]

Answer: 6

Step-by-step explanation: 2/3 of 9 = 6

6 0

3 years ago

17.45 how do you mixed numbers and reduce

Vadim26 [7]

Hello!

17.45 as a mixed fraction is 17 9/20.

If this is not correct, please comment below and I will try my best to find the right answer.

5 0

3 years ago

Read 2 more answers

Solve the system of equations by elimination 3x+4y=31 2x-4y=-6

ANEK [815]

3x + 4y = 31
2x - 4y = -6

*The +4 and -4 in the center of the equation cancel out because 4-4 = 0*

3x = 31
2x = -6
------------

*add like terms*

3x + 2x = 5x

31 - 6 = 25

So now you should have this written on your paper ... > 5x = 25

*Divide by 5 on each side*

5x = 25
_ _
5 5

x = 5

5 0

3 years ago

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