All categories

3 years ago

Y

Mathematics

1 answer:

zheka24 [161]3 years ago

5 0

Please visit this link: https://youtu.be/_0Ft9HdNg5c

You might be interested in

What does 5/6 ÷ 8.5 equal, in fractions and division form

nydimaria [60]

Answer:

5/51 or 0.098

Step-by-step explanation:

8 0

3 years ago

Read 2 more answers

Burning coal yields about 30 x 106 joules of energy per kilogram of coal burned, but only 30% of that energy goed into electrici

abruzzese [7]

Answer:

Number of bulbs which can be lit using 1 kg of coal = 9

Step-by-step explanation:

Energy yielded by burning 1 kg of coal = 30 × 106 joules

= 3180 joules

Amount of energy that can be used for electricity = 30 % of 3180 joules

= 0.30 × 3180

= 954 joules

Energy needed for lighting one bulb = Wattage of bulb × No. of hours of lighting

⇒ Energy needed for lighting one bulb = 100 × 1

= 100 joules

$\text{Now, Number of bulbs which can be lit for one hour = }\frac{954}{100}\\\\\implies\bf\textbf{Number of bulbs = }9.54\approx 9$

Hence, Number of bulbs which can be lit using 1 kg of coal = 9

4 0

3 years ago

A sample of 25 undergraduates reported the following dollar amounts of entertainment expenses last year:

marin [14]

Answer:

$Range = 85$

$\sigma = 28.71$

$Interval = [666.78, 781.62]$

Step-by-step explanation:

Given

The data for 25 undergraduates

Solving (a): Range and Standard deviation

The range is:

$Range = Highest - Least$

From the dataset:

$Highest = 772$

$Least = 687$

So:

$Range = Highest - Least$

$Range = 772-687$

$Range = 85$

The standard deviation is:

$\sigma = \sqrt{\frac{\sum(x - \bar x)^2}{n}}$

First, calculate the mean

$\bar x = \frac{769 +691 +............+715}{25}$

$\bar x = \frac{18105}{25}$

$\bar x = 724.2$

So, the standard deviation is:

$\sigma = \sqrt{\frac{(769-724.2)^2 +(691-724.2)^2 +(699-724.2)^2 +(730-724.2)^2 +............+(715-724.2)^2}{25}}$

$\sigma = \sqrt{\frac{20604}{25}}$

$\sigma = \sqrt{824.16}$

$\sigma = 28.71$

Solving (b): The interval of the 95% of the observation.

Using the emperical rule, we have:

$Interval = [\bar x - 2*\sigma, \bar x+ 2*\sigma]$

$Interval = [724.2 - 2*28.71, 724.2 + 2*28.71]$

$Interval = [666.78, 781.62]$

4 0

3 years ago

How do you find the difference between median and mean

Flura [38]

Median is the middle number. Ex:
1,3,5,7,10,13,14

The middle number is 7 because there is three numbers on either side of 7. The median would be 7.

The mean is when you add up all of the numbers and divide by the number of numbers. For example, 1,3,5,7,10,13,14
You add all of them. 1+3+5+7+10+13+14 equals 53. Then divide 53 by 7 because there are seven digits.

Median equals 7.57142857

5 0

4 years ago

Jackie deposited $315 into a bank account that earned 1.5% simple interest each year. If no money was deposited into or withdraw

Mekhanik [1.2K]

The formula for simple interest is i = p*r*t, where p is the principal, r is the interest rate as a decimal fraction, and t is the time in years.

Here, i = ($315) (0.015) (3) = $14.18 (answer)

4 0

3 years ago

Read 2 more answers