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
Alecsey [184]
3 years ago
13

A group of students calculated their average score at a spelling bee. They realized that if one of them scored 9 more points, th

eir average score would be 81 points. If one of them scored 3 points less, their average score would be 78 points. How many students were in the group?
Mathematics
1 answer:
alukav5142 [94]3 years ago
8 0

Answer: There are 4 students in the group.

Step-by-step explanation:

Let the number of students in the group be n

If one of them scored 9 more points , their average score would be 81 points.

So, our equation (1) will be

\frac{\sum x+9}{n}=81\\\\\sum x+9=81n

Similarly,

If one of them scored 3 points less, their average score would be 78 points.

So, our equation (2) will be

\frac{\sum x-3}{n}=78\\\\\sum x-3=78n

So, from equation (1) and (2) we get:

81n-9=\sum x=78n+3\\\\81n-9=78n+3\\\\81n-78n=3+9\\\\3n=12\\\\n=\frac{12}{3}\\\\n=4

Hence, there are 4 students in the group.

You might be interested in
Examine the problem below in order to calculate the value of b.
Tema [17]
B=63
You divide 1134/18
I think.......
6 0
2 years ago
Read 2 more answers
What’s the answer helpp
padilas [110]
Answer is the second option, the one that says X+1/1
8 0
3 years ago
Please I need this before 12pm
luda_lava [24]

Answer:

The required formula is:

                                                          {\displaystyle \ a_{n}=a_{1}+(n-1)d}

Step-by-step explanation:

The total number of squares of the the first term = 4

The total number of squares of the the second term = 7

The total number of squares of the the third term = 10

so,

a_1=4

a_2=7

a_3=10

Finding the common difference d

d=a_3-a_2=10-7=3

d=a_2-a_1=7-4=3

As the common difference 'd' is same, it means the sequence is in arithmetic.

So

If the initial term of an arithmetic progression is {\displaystyle a_{1}} and the common difference of successive members is d, then the nth term of the sequence (a_n) is given by:

                         {\displaystyle \ a_{n}=a_{1}+(n-1)d}

Therefore, the required formula is:

                                                          {\displaystyle \ a_{n}=a_{1}+(n-1)d}

3 0
3 years ago
Subtract the equations.
Lostsunrise [7]

Answer:

0x+2y=22

Step-by-step explanation:

Set them equal to each other, (5x+4y=25)-(5x+2y=3). Distribute the negative into the right equation, (5x+4y=25)(-5x-2y=-3). Then combine like terms to get your answer.

6 0
2 years ago
Will give brainliest.
Leno4ka [110]
Part A: y-intercept = 12 miles 


Part B: Find the average rate of change: 36 - 20/2 = 16/2 = 8 mph
This tells us that the bird can travel long distances. 


Part C: 172 - 12 = 160 miles at a rate of 8 mph
160 mi ÷ 8mph = 20 hrs

Domain of function = 0 ≤ x ≤ 20
8 0
3 years ago
Other questions:
  • Heather has a bag containing 4 marbles. 1 red, 1 blue, and 2 green. She draws 1 marble out of the bag, replaces it. And then dra
    9·2 answers
  • The track team plans to sprint 20 miles this school year.
    11·1 answer
  • What are the domain and range of the function
    14·2 answers
  • Answer this 4(−12)(−3)
    6·1 answer
  • Pleaseee help meeee 42 + 1 x 4
    14·1 answer
  • What is the additive inverse of -3.2?
    13·1 answer
  • What is 3/4 divided by 2/3<br><br> also <br> what is 1/3 divided by 4/1
    13·2 answers
  • If the sales tax rate is 7% in Texas, then how much would you pay in Houston for a coat that cost $32.00?​
    6·1 answer
  • To compare and order fractions,the fraction can be written with a​
    11·1 answer
  • What is the perimeter of the triangle?<br> units
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!