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2 years ago

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Joshua is five years older than David. Simon is four years older than Joshua and nine years older than David. Simon’s and David’

s ages added together equal 15. How old are the boys?

1 answer:

Tasya [4]2 years ago

8 0

David's age: x
Joshua: x + 5
Simon: (x+5) + 4 or x + 9

Simon's age + David's age = 15
(x+9) + (x) = 15
2x = 15 - 9
2x/2 = 6/2
x = 3

The ages of the boys:

David: x = 3 years old
Joshua: 3+5 = 8 years old
Simon: 3+9 = 12 years old

Read more on Brainly.ph - https://brainly.ph/question/1602102#readmore

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Answer: <u>Last option</u>

$Z_ {13} = 0.5,\ Z_ {17} = 2.5$

Step-by-step explanation:

The z-scores give us information about how many standard deviations from the mean the data are. This difference can be negative, if the data are n deviations to the left of the mean, or it can be positive if the data are n deviations to the right of the mean.

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Read 2 more answers

You are in charge of a crew that inspects cars. Each car takes approximately 1/2 hour for 1 person to inspect. The normal crew h

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Since each car takes 0.5 hour to be reviewed.

So, the time required to review 320 cars = 320 x 05 = 160 hours.

So, the total hours needed to inspect all 320 cars = 160 hours

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Hence , each inspectors NEEDS to work 20 hours in order to review 320 cars.

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