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qaws [65]
3 years ago
7

The Johnson twins were born nine years after their older sister. This year, the product of the three siblings ages is exactly 18

61 more than the sum of their ages. How old are the twins?
Mathematics
1 answer:
KATRIN_1 [288]3 years ago
3 0

Answer: The age of the twins is 10 years.

Step-by-step explanation:

Suppose the age of older sister be x

Let the age of twins sister be x-9, as they are born after 9 years.

Product of their ages be

x(x-9)(x-9)\\\\=x(x^2-18x+81)\\\\=x^3-18x^2+81x

Sum of their ages will be

x+x-9+x-9\\\\=3x-18

According to question,

1861+3x-18=x^3-18x^2+81x\\\\x^3-18x^2+81x-3x+18-1861=0\\\\x^3-18x^2+78x-1843=0\\\\x=19

So, Age of older sister will be 19 years.

Age of the twins will be

19-9=10\ years

Hence, the age of the twins is 10 years.

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The area of a rectangle is 91 square inches. If the length of the rectangle is 1 less than twice its width, write an equation th
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The following equation can be used to calculate the width, w, of the rectangle with the specified area: 2w²- w - 91 = 0.

<h3>What is a Rectangle's Area?</h3>

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Multiply the length by the width to obtain the area of a rectangle. The formula is as follows: A = L * W where A is the area, L denotes the length, W denotes the width, and * denotes multiplication. where A denotes area, s denotes side length, and implies multiply.

Given,

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5 0
1 year ago
Suppose a batch of metal shafts produced in a manufacturing company have a standard deviation of 1.5 and a mean diameter of 205
lawyer [7]

Answer:

the probability is 0.0750

Step-by-step explanation:

The computation of the probability is shown below;

The mean of x is

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2 years ago
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Answer:

Due to the higher Z-score, Demetria should be offered the job.

Step-by-step explanation:

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Z = \frac{X - \mu}{\sigma}

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

In this question:

Whichever applicant had grade with the highest z-score should be offered the job.

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Z = \frac{85.1 - 61.1}{12}

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