The mean of the marks in Statistics of 100 students in a class was 72 The mean of marks for boys was 75 while their number was 70 The mean of marks of girls in the class was

35

No worries! We‘ve got your back. Try BYJU‘S free classes today!

$65$

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

$68$

No worries! We‘ve got your back. Try BYJU‘S free classes today!

$86$

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B $65$
Mean marks of girls
= $\frac{T o t a l m a r k s o f a l l s t u d e n t s - T o t a l m a r k s o f b o y s}{T o t a l n u m b e r s o f g i r l s}$
= $\frac{100 \times 72 - 75 \times 70}{30} = \frac{7200 - 5250}{30}$
= $\frac{1950}{30} = 65$

Suggest Corrections

Similar questions

Q. The mean marks got by

300

students in the subject of statistics was

45

. The mean of top

100

of them was found to be

70

and the mean of last

100

was known to be

20

, then the mean of remaining

100

students is

Q. The mean marks of 10 boys in a class is 70 whereas the mean marks of 15 girls is 60. The mean marks of all the 25 students is:

In a class of 100 students, there are 70 boys whose average marks in Mathematics are 75. If the average marks of the complete class is 72, then average marks of girls is

Join BYJU'S Learning Program

The mean of the marks in Statistics of 100 students in a class was 72 The mean of marks for boys was 75 while their number was 70 The mean of marks of girls in the class was

The correct option is B $65$Mean marks of girls = Totalmarksofallstudents−TotalmarksofboysTotalnumbersofgirls= 100×72−75×7030=7200−525030 = 195030=65

The correct option is B $65$
Mean marks of girls
= $\frac{T o t a l m a r k s o f a l l s t u d e n t s - T o t a l m a r k s o f b o y s}{T o t a l n u m b e r s o f g i r l s}$
= $\frac{100 \times 72 - 75 \times 70}{30} = \frac{7200 - 5250}{30}$
= $\frac{1950}{30} = 65$