How many kg equals 10.5 g??

The heights of a maple tree and a cherry tree have a ratio of 5:2. If the maple tree grew 20 cm and 20 cm was cut off the top of

elena-14-01-66 [18.8K]

Let x be the heights of a maple tree and y be the height of the cherry tree.
We know:
 $\frac{x}{y} = \frac{5}{2}$
The new ratio is obtained like this:
 $\frac{x+20}{y-20} = \frac{3}{1}$ .
From the above equation we get $x= (y-20)\frac{3}{1} -20$ .
then $\frac{ (y-20)\frac{3}{1} -20}{y} = \frac{5}{2}$
Solving the above equation for y we get: $y=160$
So $x=400$
So the first tree is (400-160=240) more taller than cherry tree.

7 0

3 years ago

Can anybody help me with questions 17-23?

sdas [7]

5600 is number 23 helps it helps

7 0

3 years ago

Elderly drivers. In January 2011, The Marist Poll published a report stating that 66% of adults nationally think licensed driver

katrin [286]

Answer:

(a) Hence, the margin of error reported by The Marist Poll was correct.

(b) Based on a 95% confidence interval the poll does not provide convincing evidence that more than 70% of the population think that licensed drivers should be required to retake their road test once they turn 65.

Step-by-step explanation:

We are given that the Marist Poll published a report stating that 66% of adults nationally think licensed drivers should be required to retake their road test once they reach 65 years of age.

It was also reported that interviews were conducted on 1,018 American adults, and that the margin of error was 3% using a 95% confidence level.

(a) Margin of error formula is given by;

Margin of Error = $Z_(_\frac{\alpha}{2}_) \times \sqrt{\frac{\hat p(1-\hat p)}{n} }$

where, $\alpha$ = level of significance = 1 - 0.95 = 0.05 or 5%

Standard of error = $\sqrt{\frac{\hat p(1-\hat p)}{n} }$

Also, $\hat p$ = sample proportion of adults nationally think licensed drivers should be required to retake their road test once they reach 65 years of age = 66%

n = sample of American adults = 1.018

The critical value of z for level of significance of 2.5% is 1.96.

So, Margin of Error = $Z_(_\frac{\alpha}{2}_) \times \sqrt{\frac{\hat p(1-\hat p)}{n} }$

= $1.96 \times \sqrt{\frac{0.66(1-0.66)}{1,018} }$ = 0.03 or 3%

Hence, the margin of error reported by The Marist Poll was correct.

(b) Now, the pivotal quantity for 95% confidence interval for the population proportion who think that licensed drivers should be required to retake their road test once they turn 65 is given by;

P.Q. = $\frac{\hat p-p}{ \sqrt{\frac{\hat p(1-\hat p)}{n} }}$ ~ N(0,1)

So, 95% confidence interval for p = $\hat p \pm \text{Margin of error}$

= $0.66 \pm 0.03$

= [0.66 - 0.03 , 0.66 + 0.03]

= [0.63 , 0.69]

Hence, based on a 95% confidence interval the poll does not provide convincing evidence that more than 70% of the population think that licensed drivers should be required to retake their road test once they turn 65 because the interval does not include the value of 70% or more.

7 0

3 years ago

64 percent of what number is 48

sergey [27]

The answer I got was 75%

5 0

3 years ago

Find the equation of the straight line passing through the point (3,5) which is perpendicular to the line y=3x+2

Levart [38]

Answer:

the desired equation is y = (-1/3)x + 6

Step-by-step explanation:

Let the given line be A: y=3x+2

The slope of line A is m = 3.

The slope of any line B which is perpendicular to line A is the negative reciprocal of the slope of A: m = -(1/3).

The particular perpendicular line that passes through (3, 5) is then

5 = (-1/3)(3) + b, which simplifies to 5 = -1 + b, or b = 6.

Thus, the desired equation is y = (-1/3)x + 6

7 0

3 years ago