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3 years ago

Eight people enter a race. If there are no ties, in how many ways can the first two places come out

1 answer:

8 0

Since there is no ties:

The 1st place could be obtained in 8 ways (each one could be first)
Now that the 1st place is occupied, the remaining pretenders to te 2nd place are 7 people

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In The autumn 40% of the leaves on a tree are yellow and 24% of them are green the remaining 72 leaves are half yellow how many

Charra [1.4K]

Percentage of yellow leaves on a tree during Autumn = 40%

Percentage of green leaves on a tree during Autumn = 24%

Percentage of half yellow leaves on the tree during Autumn :

$= \tt100 - 40 + 24$

$= \tt 100 - 64$

$= \tt 36 \%$ Thus, the percentage of half yellow leaves on the tree during Autumn = 36%

Number of half yellow leaves on the tree = 36%

Let the total number of leaves on the tree be x.

Which means :

$= \tt36 \% \: of \: x = 72$

$= \tt \frac{36}{100} \times x = 72$

$= \tt \frac{36 \times x}{100} = 72$

$= \tt \frac{36x}{100} = 72$

$= \tt 36x = 72 \times 100$

$= \tt36x = 7200$

$= \tt x = \frac{7200}{36}$

$\color{plum} = \tt \: x = 200$

Thus, total number of leaves on the tree = 200

Number of yellow leaves on the tree :

$= \tt40 \% \: \: of \: \: 200$

$= \tt \frac{40}{100} \times 200$

$= \tt \frac{40 \times 200}{100}$

$= \tt \frac{8000}{100}$

$\color{plum} \tt = 80 \: yellow \: \: leaves$

Thus, total number of yellow leaves on the tree = 80

Number of green trees on the tree :

$= \tt24 \% \: \: of \: \: 200$

$= \tt \frac{24}{100} \times 200$

$= \tt \frac{24 \times 200}{100}$

$= \tt \frac{4800}{100}$

$\color{plum} = \tt 48 \: green \: \: leaves$

Thus, the total number of green leaves on the tree = 48

Since the sum of all types of leaves form 200[80+48+72=200], we can conclude that we have found out the correct number of each type of leaf.

▪︎Therefore, <em>the total number of leaves on the tree = 200</em>

3 0

3 years ago

Help&EXPLAIN <br> •••••••••••••••••••<br> Help plz

Stolb23 [73]

Answer:

diameter = 2.5 feet

Step-by-step explanation:

Circumference of a circle is given as C = πd

Circumference of the tree trunk = 7.85 ft

π = 3.14

Diameter of the tree trunk = d

Thus:

7.85 = 3.14*d

Divide both sides by 3.14

7.85/3.14 = 3.14*d/3.14

2.5 = d

d = 2.5 ft

3 0

3 years ago

A circle with an area 9pi has a sector with a central angle of 1/9pi what is the area of the sector

ludmilkaskok [199]

Answer:

½pi or 0.5pi units²

Step-by-step explanation:

Area : angle

9pi : 2pi

x : pi/9

9pi/2pi = x/(pi/9)

4.5 × pi/9 = x

x = ½pi or 0.5pi units²

8 0

3 years ago

If Joe makes 16 out of 40 free throws in a

abruzzese [7]

The answer would be 6.4% because you have to do 16% of 40 and it will give you 6.4 and as a percent it is 640%

8 0

3 years ago

Every evening, two weather stations issue weather forecast for the next day. The weather forecasts are independent. On average,

EleoNora [17]

Answer:

The probability is 0.6923

Step-by-step explanation:

Let's call R the event that the next day rains, S the event that the next day has sunny weather, R2 the event that the station 2 predicts rain and S1 the event that station 1 predict sunny weather.

The probability that the next day has sunny weather given that station 1 predicts sunny weather for the next day and station 2 predicts rain is calculated as:

P(S/S1∩R2) = P(S∩S1∩R2)/P(S1∩R2)

Where P(S1∩R2) = P(R∩S1∩R2) + P(S∩S1∩R2)

So, the probability P(R∩S1∩R2) that the next day rains, Station 1 predicts sunny weather and Station 2 predicts Rain is calculate as:

P(R∩S1∩R2) = 0.5 * 0.1 * 0.8 = 0.04

Because 0.5 is the probability that the next day rains, 0.1 is the probability that station 1 predicts sunny weather given that it is going to rain and 0.8 is the probability that station 2 predicts rain given that it is going to rain.

At the same way, the probability P(S∩S1∩R2) that the next day has sunny weather, Station 1 predicts sunny weather and Station 2 predicts Rain is calculate as:

P(S∩S1∩R2) = 0.5 * 0.9 * 0.2 = 0.09

Then, the probability P(S1∩R2) that station 1 predicts sunny weather for the next day, whereas station 2 predicts rain is:

P(S1∩R2) = 0.04 + 0.09 = 0.13

Finally, P(S/S1∩R2) is:

P(S/S1∩R2) = 0.09/0.13 = 0.6923

6 0

3 years ago