If m < apd =109 and m <1=17 then m<bpd=

Traffic speed: The mean speed for a sample of cars at a certain intersection was kilometers per hour with a standard deviation o

aliina [53]

Answer:

Step-by-step explanation:

Hello!

X₁: speed of a motorcycle at a certain intersection.

n₁= 135

X[bar]₁= 33.99 km/h

S₁= 4.02 km/h

X₂: speed of a car at a certain intersection.

n₂= 42 cars

X[bar]₂= 26.56 km/h

S₂= 2.45 km/h

Assuming

X₁~N(μ₁; σ₁²)

X₂~N(μ₂; σ₂²)

and σ₁² = σ₂²

<em>A 90% confidence interval for the difference between the mean speeds, in kilometers per hour, of motorcycles and cars at this intersection is ________.</em>

The parameter of interest is μ₁-μ₂

(X[bar]₁-X[bar]₂)± $t_{n_1+n_2-2}$ * $Sa\sqrt{\frac{1}{n_1} +\frac{1}{n_2} }$

$t_{n_1+n_2-2;1-\alpha /2}= t_{175; 0.95}= 1.654$

$Sa= \sqrt{\frac{(n_1-1)S_1^2+(n_2-1)S_2^2}{n_1+n_2-2} } = \sqrt{\frac{134*16.1604+41*6.0025}{135+42-2} } = 3.71$

[(33.99-26.56) ± 1.654 *( $3.71*\sqrt{\frac{1}{135} +\frac{1}{42} }$ )]

[6.345; 8.514]= [6.35; 8.51]km/h

<em>Construct the 98% confidence interval for the difference μ₁-μ₂ when X[bar]₁= 475.12, S₁= 43.48, X[bar]₂= 321.34, S₂= 21.60, n₁= 12, n₂= 15</em>

$t_{n_1+n_2-2;1-\alpha /2}= t_{25; 0.99}= 2.485$

$Sa= \sqrt{\frac{(n_1-1)S_1^2+(n_2-1)S_2^2}{n_1+n_2-2} } = \sqrt{\frac{11*(43.48)^2+14*(21.60)^2}{12+15-2} } = 33.06$

[(475.12-321.34) ± 2.485 *( $33.06*\sqrt{\frac{1}{12} +\frac{1}{15} }$ )]

[121.96; 185.60]

I hope this helps!

3 0

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Brittany's mom gave her $15.00 to buy school supplies. Brittany needs to buy 3 notebooks and some mechanical pencils. If each no

ElenaW [278]

Answer:

4 mechanical pencils

Step-by-step explanation:

Each notebook is worth $2.99

So buying 3 of the notebooks would leave her with $8.97

Then, $15.00 - $8.97= $6.05

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Jodi is cutting out pieces of paper that measure 8 1/2 inches by 11 inches from a larger sheet of paper that has an area of 1000

attashe74 [19]

10 diffhhjjjkfdffyiihgfgghjjhggghh

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A business had sales last year of $139,526,000. Write the value of the 9 digit in this number. _________________________________

tresset_1 [31]

Oooooooonnnnnneeeeeeeemmmmmmmmiiiiilllllllliiiiieeee

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You bought $2000 worth of stocks in 2012. The value of the stocks has been decreasing by 10% each year. What will your stock be

goblinko [34]

Answer:

that is the solution to the question

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