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3 years ago

I need help plz:((((((((((

Mathematics

1 answer:

pashok25 [27]3 years ago

3 0

Answer:

a) $y=\frac{28}{75}(x-1900)+47.3$

b) 86.5 years

Step-by-step explanation:

All values are rounded to 2 decimal places

a) We can find line by using y =mx+b

$y=mx+b\\m=\frac{y^{2}-y^{1} }{x^{2}-x^{1}}\\m=\frac{69.7-47.3}{1960-1900} \\m=\frac{22.4}{60} \\m=\frac{28}{75}\\c=y-intercept\\y-intercept=47.3\\y=\frac{28}{75} (x-1900)+47.3$

Therefore the line of best fit is $y=\frac{28}{75}(x-1900)+47.3\\$

b) We can do this by using the formula of the best fit line to estimate the life expectancy of someone born in 2005

$y=\frac{28}{75}(x-1900)+47.3\\y=\frac{28}{75}(2005-1900)+47.3\\y=\frac{28}{75}\times105+47.3\\y=86.5$

Therefore the estimated life expectancy of someone born in 2005 is 86.5 years

PS. Please give brainliest answer this was a lot of working out

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3 years ago

The lengths of nails produced in a factory are normally distributed with a mean of 3.34 centimeters and a standard deviation of

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Now converting, we get

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3 years ago

A large fish tank at an aquarium needs to be emptied so that it can be cleaned. When its

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Answer:

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From statement, we have the following three expressions:

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3 years ago

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