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King
 4 years ago
: Help..............In a school a certain number of boys and girls attend a certain examination. The mean mark of the boys was 40 and the mean mark of the girls was 60.Mean of all students is 48.Find the number of boys and girls in a class of 100.
King
 4 years ago
: Help..............In a school a certain number of boys and girls attend a certain examination. The mean mark of the boys was 40 and the mean mark of the girls was 60.Mean of all students is 48.Find the number of boys and girls in a class of 100.

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wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0(40x+60y)/100=48 x+y=100

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0solve two simoultaneous eq

King
 4 years ago
Best ResponseYou've already chosen the best response.0not possible sorry wrong answer x+y needs to be 100

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0sorry i mean to say galx 40

King
 4 years ago
Best ResponseYou've already chosen the best response.0oh ok but how did u get first two equations....xplain

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0listen what will be mean of marks? total marks divided by candidate

King
 4 years ago
Best ResponseYou've already chosen the best response.0and what is x and what is y?

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0x is boys , y is number of galx

King
 4 years ago
Best ResponseYou've already chosen the best response.0yeah but how 40 * x and 60 * y?

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0so the total marks is number of boys into their marks+number of galx nto their mean marks then divided by total number of students that s 100

King
 4 years ago
Best ResponseYou've already chosen the best response.0why is 40 multiplied by x and 60 multiplied into y?

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.040 is the mean marks of boys and x is the total number of boys in class and y is total number of gals ad 60 is the mean marks of gal

King
 4 years ago
Best ResponseYou've already chosen the best response.0yeah so why do we multiply?

AnwarA
 4 years ago
Best ResponseYou've already chosen the best response.0OK. Let \(n\) and \(m\) be the number if boys and girls respectively, then \(40 n\) is the total points that boys scored, and \(60m\) is the total of the girls. We can then write \(\frac{40n+60m}{m+n}=48\). We also have \(m+n=100\). Solve them to find m and n.

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0we multiply to get the total number of marks like suppose there are 3 students in class and their mean mark is 90 so how we will get the marks obtained by class in total as in we want to add the marks of all the student

AnwarA
 4 years ago
Best ResponseYou've already chosen the best response.0If you solve them, you will get \(n=70 \text{ boys, and } m=30 \text{ girls}\).

King
 4 years ago
Best ResponseYou've already chosen the best response.0wasiq why will we multiply if 3 students are there then mmean is x1+x2+x3/3=90

AnwarA
 4 years ago
Best ResponseYou've already chosen the best response.0Oh sorry, I solved them for \(46\), not \(48\). Wait a sec.

King
 4 years ago
Best ResponseYou've already chosen the best response.0yea anwser is rite but i dont understand why we multiply...

asnaseer
 4 years ago
Best ResponseYou've already chosen the best response.1the mean of the these 3 numbers: 12,14,16 is calculated as:\[\frac{12+14+16}{3}=\frac{42}{3}=14\]the total of those 3 numbers is: 12+14+16=42, which is the same as the mean times the number of numbers you have: 14*3=42

wasiqss
 4 years ago
Best ResponseYou've already chosen the best response.0king u r dumb, sorry to say bt tru

asnaseer
 4 years ago
Best ResponseYou've already chosen the best response.1so, if you are given the mean and the number of items, you can always work out the total number of items as (mean)*(number of items)

AnwarA
 4 years ago
Best ResponseYou've already chosen the best response.0Let me explain it to you. Assume we have 5 students, and their mean is 50. We can write that as \(\large{\frac{x_1+x_2+x_3+x_4+x_5}{5}=50}\). Now if we want to find the sum of the points that all the 5 student scored, we just multiply both sides by \(5\) to get \(\large {x_1+x_2+x_3+x_4+x_5=5\times 50}\). Makes sense?

asnaseer
 4 years ago
Best ResponseYou've already chosen the best response.1sorry "the total of all the items"

King
 4 years ago
Best ResponseYou've already chosen the best response.0oh ok thnx anwar and asnaseer thnk u very much

asnaseer
 4 years ago
Best ResponseYou've already chosen the best response.1no problem  always glad to help
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