The mean marks obtained by a class of 56 Students is 62 the mean marks of a half of the students marks is found to 54 then the mean Marks of remaining half students marks??
Answers
Answer:
70
Step-by-step explanation:
The mean marks obtained by a class of 56 Students is 62
x1+x2+------------x56
------------------------------- =62 ---------eq1
56
the mean marks of a half of the students marks is found to 54
x1+x2+------------x28
------------------------------- =54
28
x1+x2+--------------+x28 = 54×28------------eq2
then the mean Marks of remaining half students marks is
x29+x30+------------x56
------------------------------- = ?
28
by taking eq1
x1+x2+-----+x28+x29+-------+x56
------------------------------------------- = 62
56
x1+x2+-----+x28 x29+-------+x56
---------------------- +--------------------- = 62 -------eq3
56 56
by substituting eq2 in eq3
54×28 x29+-------+x56
---------------------- +------------------------ = 62
56 56
x29+-------+x56
= 27+ --------------------- = 62
56
x29+-------+x56
= --------------------- = 2×(62-27)
28
x29+-------+x56
= -------------------------- = 70
28
the mean Marks of remaining half students marks is 70