Question

If the mean of the marks of five students is 33 and
that of the marks of four of them is 32.5, then find the
marks obtained by fifth student.
​

Answer 1

mean of marks of 5 students is 33 .

So total marks of 5 students/ no. of students = 33

which gives

total marks of 5 students / 5 = 33

so total marks of 5 students = 33 X 5 = 165.

Now mean of marks of 4 students is 32.5

i.e total marks of 4 students/ no. of students = 32.5

so, total marks of 4 students = 32.5 X 4 = 130

Now we know the total marks of 4 students and total marks of 5 students. Thus the marks of the 5 th student is the difference between these total marks.

Hence, 165 - 130 = 35 marks is the marks obtained by the fifth student.

Answer 2

Answer:

Step-by-step explanation:

mean of marks of 5 students is 33 .

So total marks of 5 students/ no. of students = 33

which gives

total marks of 5 students / 5 = 33

so total marks of 5 students = 33 X 5 = 165.

Now mean of marks of 4 students is 32.5

i.e total marks of 4 students/ no. of students = 32.5

so, total marks of 4 students = 32.5 X 4 = 130

Now we know the total marks of 4 students and total marks of 5 students. Thus the marks of the 5 th student is the difference between these total marks.

Hence, 165 - 130 = 35 marks is the marks obtained by the fifth student.