Algebra 1 word problem help!!!?
A class of 25 students takes a test and the average grade is 72. One student's score was marked as a 36 when it was really an 86. What would the new average be?
I have no clue how to go about solving that. Can you tell me the answer and show how you got it? Thanks.
Comments
The mean (average) of a list of numbers (in this context, the test scores) is calculated by dividing the sum of every number in a list (the total of every student's score) by the number of numbers in the list (the frequency, or the number of students). Therefore, by rearranging this we find that the sum of the numbers can be calculated by multiplying the frequency by the mean. In the context of your question, this gives us 25*72, which comes to 1800.
As the mistaken score is 50 more than it was previously recorded as, we add 50 to our old total to find our new, correct total, which is 1850. Then it is a simple matter of finding the correct mean by dividing the new total by the number of students, the calculation for which would obviously be 1850/25, which comes to 74. Therefore, the correct average is 74.
(25*72)+(86-36)
then divide by 25
answer is 74
average = a
total = t
number = n
a=t/n
well you have n and a
so solve for t
a*n=t, or 72*25=1800, plus the additional infomation of +50
1850/25 = 74
First, check out what you're asked to discover, the as quickly as a year fee of activity that's 'r' in the equation you're given. the subsequent step is to set up the equation in know to r. r=..... subsequently the equation would be r=I/pt. in the question it states, 'you invested $1200' that's 'p' in the equation. hence p=$1200 the subsequent area of the question says 'for a era of six years' that's 't' in the equation. hence t=6 The final area of the equation is 'earned $396 uncomplicated activity' that's 'I' in the equation. hence I=$369 Then this is in basic terms putting all of this into the equation we've rearranged. So if r=I/pt then r=$369/(6x$1200) Answ: r=0.05125 keep in mind, you're constantly given sufficient education in the question to get the respond. If it enables suitable down what education you be attentive to from th question in the previous you attempt to respond to it. desire this helped!
you need to know all the other scores aswell as tj's
All i know is that the average will increase