Can someone help me with this?!

Terry and Callie do word processing. For a certain prospectus Callie can prepare it two hours faster than Terry can. If they wor

Dahasolnce [82]

Time taken by jerry alone is 10.1 hours

Time taken by callie alone is 8.1 hours

Solution:

Given:- For a certain prospectus Callie can prepare it two hours faster than Terry can

Let the time taken by Terry be "a" hours

So, the time taken by Callie will be (a-2) hours

Hence, the efficiency of Callie and Terry per hour is $\frac{1}{a-2} \text { and } \frac{1}{a} \text { respectively }$

If they work together they can do the entire prospectus in five hours

$\text {So, } \frac{1}{a-2}+\frac{1}{a}=\frac{1}{5}$

On cross-multiplication we get,

$\frac{a+(a-2)}{(a-2) \times a}=\frac{1}{5}$

$\frac{2 a-2}{(a-2) \times a}=\frac{1}{5}$

On cross multiplication ,we get

$\begin{array}{l}{5 \times(2 a-2)=a \times(a-2)} \\\\ {10 a-10=a^{2}-2 a} \\\\ {a^{2}-2 a-10 a+10=0} \\\\ {a^{2}-12 a+10=0}\end{array}$

using quadratic formula:-

$x=\frac{-b \pm \sqrt{b^{2}-4 a c}}{2 a}$

$x=\frac{12 \pm \sqrt{144-40}}{2}$

$\begin{array}{l}{x=\frac{12 \pm \sqrt{144-40}}{2}} \\\\ {x=\frac{12 \pm \sqrt{104}}{2}} \\\\ {x=\frac{12 \pm 2 \sqrt{26}}{2}} \\\\ {x=6 \pm \sqrt{26}=6 \pm 5.1} \\\\ {x=10.1 \text { or } x=0.9}\end{array}$

If we take a = 0.9, then while calculating time taken by callie = a - 2 we will end up in negative value

Let us take a = 10.1

So time taken by jerry alone = a = 10.1 hours

Time taken by callie alone = a - 2 = 10.1 - 2 = 8.1 hours

3 0

3 years ago

I only need Q d please (the last question)

irinina [24]

Answer:

December at -10

Step-by-step explanation:

first you rule out all positive numbers

then you finder the biggest number with a negative side and that is you lowest temperature

3 0

3 years ago

1+2= 3+4 4=3 )+0 you dont have to answer just put a random letter or something

Alina [70]

Answer:

3

7

last one doesn't even make sense

3 0

2 years ago

Please help me on these questions.

KonstantinChe [14]

Answer:

1C

2A

3B

4D

Step-by-step explanation:

I did it

5 0

3 years ago

The number of surface flaws in plastic panels used in the interior of automobiles has a Poisson distribution with a mean of 0.05

Tresset [83]

Answer:

(a) Probability that there are no surface flaws in an auto's interior is 0.6065 .

(b) If 10 cars are sold to a rental company, what is the probability that none of the 10 cars has any surface flaws is 0.00673 .

Step-by-step explanation:

We are given that the number of surface flaws in plastic panels used in the interior of automobiles has a Poisson distribution with a mean of 0.05 flaws per square foot of plastic panel.

Let X = Distribution of number of surface flaws in plastic panels

So, X ~ Poisson( $\lambda$ )

The mean of Poisson distribution is given by, E(X) = $\lambda$ = 0.05

which means, X ~ Poisson(0.05)

The probability distribution function of a Poisson random variable is:

$P(X=x)=\frac{e^{-\lambda}\lambda^{x}}{x!}; for x=0,1,2,3...$

Now, we know that $\lambda$ for per square foot of plastic panel is 0.05 and we are given that an automobile interior contains 10 square feet of plastic panel.

Therefore, for 10 square foot of plastic panel is = 10 * 0.05 = 0.5

(a) Probability that there are no surface flaws in an auto's interior =P(X=0)

P(X = 0) = $\frac{e^{-0.5}*0.5^{0}}{0!}$ = $e^{-0.5}$ = 0.6065

(b) If 10 cars are sold to a rental company, what is the probability that none of the 10 cars has any surface flaws = $P(X = 0)^{10}$

So, $P(X = 0)^{10}$ = $0.6065^{10}$ = 0.00673

8 0

3 years ago