WORD PROBLEMS on Statistics 9 for Class 9 and 10
Question for practice
The following questions are more helpful for class tenth students for all boards.
The following questions are more helpful for class tenth students for all boards.
Questions 9. The average score of boys in an examination of the school is 71 and that of girls is 73. The average score of the school in that examination is 71.8. Find the ratio of the number of boys to the number of girls that appeared in the examination.
Submit your answer here in the comments or wait for answer
Questions 9. The average score of boys in an examination of the school is 71 and that of girls is 73. The average score of the school in that examination is 71.8. Find the ratio of the number of boys to the number of girls that appeared in the examination.
Submit your answer here in the comments or wait for answer
let the total marks of boys be a
ReplyDeletelet the total boys be x
a/x=71
a=71x
let the total marks of girls be b
let the total boys be y
b/y=73
b=73y
(a+b)/(x+y) = 71.8
71x+73y=71.8x + 71.8y
73y-71.8y=71.8x-71x
1.2y = 0.8x
x/y = 1.2/0.8
x/y = 3/2
ratio of no. of boys to girls = 3:2
Let the total no. of marks obtained by boys be a
ReplyDeleteLet the total no. of boys be x
a/x=71
a=71x
Let the total no. of marks obtained by girls be b
Let the total no. of girls be y
b/y=73
b=73y
total no. of students/total no. of marks = avg. score
(a+b)/(x+y) = 71.8
71x+73y/(x+y)= 71.8
71x+73y=71.8x + 71.8y
73y-71.8y=71.8x-71x
1.2y = 0.8x
x/y = 1.2/0.8
x/y = 3/2
Ratio of no. of boys to girls that appeared for the exam = 3:2
LET THE TOTAL MARKS OF BOYS BE x.
ReplyDeleteLET THE TOTAL NUMBER OF BOYS BE y.
x/y=71
THEREFORE,x=71y
LET THE TOTAL MARKS OF GIRLS BE z.
LET THE TOTAL NUMBER OF GIRLS BE w.
z/w=73
THEREFORE,z=73w
TOTAL NUMBER OF STUDENTS=TOTAL MARKS/AVERAGE SCORE
=>(a+b)/(x+y)=71.8
=>71x+73y/(x+y)=71.8
=>71x+73y=71.8x+71.8y
=>73y-71.8y=71.8x-71x
=>1.2y=0.8x
=>x/y=1.2/0.8
=>x/y=3/2
THEREFORE, THE RATIO OF NUMBER OF BOYS TO NUMBER OF GIRLS THAT APPEARED FOR THE EXAM=3:2
LET TOTAL MARKS OF BOYS BE m
ReplyDeleteLET TOTAL NUMBER OF BOYS BE n.
m/n=71
m=71n
LET THE TOTAL MARKS OF GIRLS BE a
LET THE TOTAL NUMBER OF GIRLS BE b .
a/b=73
a=73b
TOTAL NUMBER STUDENTS=TOTAL MARKS/AV. SCORE
(m+a)/(n+b) = 71.8
71n+73b/(n+b)= 71.8
71n+73b=71.8n + 71.8b
73b-71.8b=71.8n-71n
1.2b = 0.8n
b/n = 1.2/0.8
b/n = 3/2
Ratio of no. of boys to girls that appeared
the exam = 3:2