The area of the square is 144 square inches. What is the area of the circle, to the nearest square inch? Use 3. 14 for

Mr. Toshio lent out 11 rulers at the beginning of class, collected 4 rulers in the middle of class, and gave out 7 at the end of

Drupady [299]

Mr. Toshio had 32 rulers. 32-11 = 21 rulers. 21+4 = 25 rulers. and 25-7 = 18 rulers

8 0

4 years ago

Read 2 more answers

Suppose on a certain test, fifty students earn a perfect score and fifty students earn a zero. determine the mean grade and stan

kodGreya [7K]

Answer:

Mean=50.

standard deviation=50.

Step-by-step explanation:

Let the perfect score be 100.

The mean(average) of a data is given by: $Mean=\frac{sum of data points}{number of data points}$

Here the number of data points are 100. out of which 50 attains a value 100,and 50 attains value 0.

so, sum of data points=50×100+50×0=5000.

$Mean=\frac{5000}{100}$

Mean=50.

"Now the standard deviation of data points are calculated by firstly subtracting mean from every entry and then square the number and take it as new entry and calculate the mean of the new data entry and lastly taking the square root of this new mean".

Here if 50 is subtracted from each entry the new entry will have 50 entries as '50' and 50 entries as '-50'.

next on squaring we will have all the 100 entries as '2500'.

now the mean of these entries is: $\frac{2500\times100}{100}$

=2500

taking it's squareroot we have $\sqrt{2500}=50$

Hence, standard deviation=50.

5 0

4 years ago

Read 2 more answers

g The distribution of heights of 7-year-old girls is approximately normally distributed with a mean of 47.7 inches and a standar

Lana71 [14]

Answer:

a) 90th percentile

b) X = 51.43 ( Sophia's height ) , Amy's height = 50.92

c) 0.2394

d) 46.44 inches

Step-by-step explanation:

mean value( u ) = 47.7 inches

std ( σ )= 2.4 inches

Amy height = 1.34 std above mean value

Sophia height = 94th percentile of height distribution

A ) what percentile is Amy's height

To Calculate the percentile of Amy's height

P( X ≤ 50.916 ) = P( (X-µ)/σ ) ≤ (50.916-47.7) /2.4)

=P(Z ≤ 1.340 ) = 0.9099 = 90th percentile

B) How Amy's height compare to Sophia's

The proportion given based on Sophia's height = 0.94

z -value at the proportion ( 0.94 ) = 1.55 ( from excel )

note z-value can be calculated using = ( x - µ ) / σ

therefore: X (Sophia's height ) = zσ + µ= (1.55 * 2.4) + 47.7

X = 51.43 ( Sophia's height ) , Amy's height = 50.92

C) percentage expected to be taller than 49.4 inches

P ( X ≥ 49.40 ) = P( (X-µ)/σ) ≥ (49.4-47.7) / 2.4)

= P(Z ≥ 0.708 )

= P( Z < -0.708 )

= 0.2394

D) Below what height are the shortest 30% of 7-year old girls

( u ) = 47.7 inches

std ( σ )= 2.4 inches

given proportion = 30% = 0.3

The z value at 0.3 = -0.52 ( from excel )

to calculate for X ( height ) we have to apply the formula used to determine z value

z= (x-µ) /σ

hence : X = (Z * σ) + u = (-0.52 * 2.4 ) + 47.7

X = 46.44

below 46.44 inches lies about 30% of 7 year old girls height

6 0

3 years ago

Ali and Ayesha shared an amount of money in the ratio 5:6. Ali received 20 bucks.How much did Ayesha receive?

Mars2501 [29]

Answer:

Your answer is $24

Step-by-step explanation:

5*4 is 20, so all that you have to do it 6*4

8 0

3 years ago

PLEASEEEE HELP I WILL MAKE YOU BRAINIEST

Bezzdna [24]

Answer:

14

Step-by-step explanation:

Because right angles are 90 degrees, we need to subtract 34 from 90 which gets us 56. That means 56 = 4x, so 56/4 = 14, therefore X = 14.

Hope this helps!

4 0

3 years ago

Read 2 more answers