1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Oksana_A [137]
3 years ago
14

The average marks of the first 10 students are 17 and that of the next 15 students is 18. find the mean of 25 students?

Mathematics
1 answer:
Ray Of Light [21]3 years ago
3 0

Answer:

The mean of 25 students is 17.6

Step-by-step explanation:

The formula of the mean (average) is mean (average) = \frac{S}{N} , where S is the sum of the data, and N is the number of the data

∵ The average marks of the first 10 students are 17

- That means the mean is 17 and the number of students is 10

∴ Average = 17

∴ N = 10

∵ Average = \frac{S}{N}

- Substitute average by 17 and N by 10

∴ 17 = \frac{S}{10}

- Multiply both sides by 10

∴ 170 = S

∴ The sum of the marks of the first 10 students is 170

∵ The average of the next 15 students is 18

∴ Average = 18

∴ N = 15

- Substitute average by 18 and N by 15

∴ 18 = \frac{S}{15}

- Multiply both sides by 15

∴ 270 = S

∴ The sum of the marks of the next 15 students is 270

Now to find the mean of 25 students and the two sums and divide the answer by 25

∵ S = 170 + 270

∴ S = 440

∵ N = 25

∴ Mean = \frac{440}{25}

∴ Mean = 17.6

The mean of 25 students is 17.6

You might be interested in
Sanjay can travel 342 miles in 6 hours. At this rate, how many miles can he travel in 5 hours?
MatroZZZ [7]

Answer:

57 miles

Step-by-step explanation:

342 divided by 5 equals 57 miles

8 0
3 years ago
PLEASE HELP WILL MARK BRAINLIEST!!!!
podryga [215]
Last Choice is the answer
7 0
2 years ago
Can someone help me correct number 6 please and thank you! Please Explain and Show Your Work!
NNADVOKAT [17]

Answer:

You have your x and y mixed up

Step-by-step explanation:

Look at your table.  You labeled y1 and y2 where the x's are.  y2 = 8, y1 = 4, x2 = 12 and x1 = 6.  The slope then is (8-4)/(12-6) which is 4/6 or 2/3.  You did run over rise instead of rise over run.  Be careful.  I see that a lot when I teach the concept to beginners.  

4 0
3 years ago
Solve.<br><br> one-thirds – 6 &lt; 24
GREYUIT [131]

Answer:

90

Step-by-step explanation:

6 0
2 years ago
Read 2 more answers
The 1,840 rock concert tickets sold were twice the amount of jazz concert tickets sold. <br><br>​
Vanyuwa [196]
Ur gay. Jeydydhushwusfb
5 0
2 years ago
Other questions:
  • What is the value of x?
    11·1 answer
  • Describe the dimension of two different prisms that each have a volume of 2,400cubic centimeters. Then draw each prism.
    15·1 answer
  • Plato delivered 1743 orations, whereas Aristotle delivered only 1234. How many
    14·2 answers
  • What is the place of the 7 in 73.87
    11·2 answers
  • Elizabeth brought a box of donuts to share. There are​ two-dozen (24) donuts in the​ box, all identical in​ size, shape, and col
    10·1 answer
  • 3ln(2x) + 7 = 15. how do I do this<br>​
    15·1 answer
  • Solve the following inequality:
    8·2 answers
  • The length of an Airbus A300 aeroplane is 54 m.
    12·1 answer
  • Fatima opened a savings account with $7,500. She decided to deposit that same amount semiannually. This account earns 3.975% int
    7·1 answer
  • The length of rectangular garden is 8 feet longer than the width. If the area of the garden is 20 square feet, find the length a
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!