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2 years ago

Need help with this assignment

Mathematics

1 answer:

OLEGan [10]2 years ago

5 0

Answer:

The answer is

$- 11b {}^{2} + 4b - 14$

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You always need some time to get up after the alarm has rung. You get up from 10 to 20 minutes later, with any time in that inte

Mama L [17]

Answer:

a) P(x<5)=0.

b) E(X)=15.

c) P(8<x<13)=0.3.

d) P=0.216.

e) P=1.

Step-by-step explanation:

We have the function:

$f(x)=\left \{ {{\frac{1}{10},\, \, \, 10\leq x\leq 20 } \atop {0, \, \, \, \, \, \, otherwise }} \right.$

a) We calculate the probability that you need less than 5 minutes to get up:

$P(x$

Therefore, the probability is P(x<5)=0.

b) It takes us between 10 and 20 minutes to get up. The expected value is to get up in 15 minutes.

E(X)=15.

c) We calculate the probability that you will need between 8 and 13 minutes:

$P(8\leq x\leq 13)=P(10\leqx\leq 13)\\\\P(8\leq x\leq 13)=\int_{10}^{13} f(x)\, dx\\\\P(8\leq x\leq 13)=\int_{10}^{13} \frac{1}{10} \, dx\\\\P(8\leq x\leq 13)=\frac{1}{10} \cdot [x]_{10}^{13}\\\\P(8\leq x\leq 13)=\frac{1}{10} \cdot (13-10)\\\\P(8\leq x\leq 13)=\frac{3}{10}\\\\P(8\leq x\leq 13)=0.3$

Therefore, the probability is P(8<x<13)=0.3.

d) We calculate the probability that you will be late to each of the 9:30am classes next week:

$P(x>14)=\int_{14}^{20} f(x)\, dx\\\\P(x>14)=\int_{14}^{20} \frac{1}{10} \, dx\\\\P(x>14)=\frac{1}{10} [x]_{14}^{20}\\\\P(x>14)=\frac{6}{10}\\\\P(x>14)=0.6$

You have 9:30am classes three times a week. So, we get:

$P=0.6^3=0.216$

Therefore, the probability is P=0.216.

e) We calculate the probability that you are late to at least one 9am class next week:

$P(x>9.5)=\int_{10}^{20} f(x)\, dx\\\\P(x>9.5)=\int_{10}^{20} \frac{1}{10} \, dx\\\\P(x>9.5)=\frac{1}{10} [x]_{10}^{20}\\\\P(x>9.5)=1$

Therefore, the probability is P=1.

3 0

2 years ago

Richard buys one tooth cleaning kit for $25 and a toothbrush for $15. He spends the rest of his money on body soap. He has $80 a

wariber [46]

He can buy up to 8 bodies of soap.
I hope this helps!

8 0

3 years ago

Read 2 more answers

How do I know if two ratios are equal to make a proportion

AfilCa [17]

One way to see if two ratios are proportional is to write them as fractions and then reduce them. If the reduced fractions are the same, your ratios are proportional.

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2 years ago

A grid model with 100 squares. 73 squares are shaded. What percent of the model is shaded? What is the equivalent ratio? What is

viva [34]

Answer:

73%

Step-by-step explanation:

First, you'll divide the total squares by 100 to get how much is one percent. Then, you divide the shaded squares by the value of 1%. And you'll get how many percents are shaded.

For equivalent decimal, you divide the number by 100.

Then for equivalent decimal, you get the percent and 100.

$p =100/100=1\\73/1=73\\=0.73\\=\frac{73}{100}$

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2 years ago

My brain is too tired to function someone save me

lina2011 [118]

Answer:

(3,2)

Step-by-step explanation:

Hope I helped

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2 years ago