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
Dahasolnce [82]
3 years ago
5

Plz help its due TOMMOROW​

Mathematics
1 answer:
sashaice [31]3 years ago
4 0

Answer:

  86%

Step-by-step explanation:

Let g represent the mean mark for the 10 girls in the class. Then the mean mark for the class was ...

  10g +20(62%) = 30(70%)

  g = 3(.7) -2(.62) . . . . . . . . . divide by 10 and subtract 2(.62)

  g = .86 = 86%

The mean mark for girls was 86%.

_____

You can do this in your head if you consider it in terms of deviations from the mean. The second equation above can be rewritten and factored as ...

  g = 70% +2(70% -62%)

That is, because there are 2 boys for every girl, the girl's score is above the mean by an amount that is 2 times the amount that the boy's score is below the mean. The boys' score is below by 8%, so the girls' score is above by 16%, so is 86%.

You might be interested in
Two cars are 750 miles apart and start moving towards each other. One car moves with the average speed of 40 mph and the other i
____ [38]
They will meet at 10:45 exactly.
5 0
3 years ago
Read 2 more answers
What is the solution of the equation sqrt 2 x+4-sqrt x=2
ivann1987 [24]
There are 2 answers to this 

x=0 
x=16
3 0
3 years ago
Is 6xy2 is the greatest common factor of 12xy2, 36x2y2, and 42xy4  
NeX [460]

Answe

Step-by-step explanation:

8 0
3 years ago
A point's coordinates are changed from (–7, –2) to (–7, 2). What effect does this have on the location of the point
Inessa [10]
It will move it from one section to another and make the x axis 4 units more to the right
7 0
3 years ago
When you flip a biased coin the probability of getting a tail is 0.75.
Blababa [14]

Answer:

180

Step-by-step explanation:

It's 180 because 75% of 240 is 180.

5 0
1 year ago
Other questions:
  • HELP! WILL MARK BRAINLIEST
    12·2 answers
  • 274 faculty surveyed regarding their plans for the weekend 126 plan to grade papers 132 plan to attend game 130 plan to do chore
    13·1 answer
  • I cannot find the answer to 10x + 18 < -2, help anyone?
    13·1 answer
  • What's 2/5 in decimal
    15·1 answer
  • Brady wants to purchase a skateboard that costs $245. So far, he has saved $98 and plans to save
    5·1 answer
  • Can I please get help in number 13.
    15·2 answers
  • Read the ques
    8·1 answer
  • A manager is comparing the cost of buying ball caps with the team emblem from two different companies. Company X charges a $50 f
    12·1 answer
  • How do your write a feaction with a denominator of 20 as a decimal?​
    12·1 answer
  • Please help with this question !!
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!