Question

In a class test, in mathematics, $10$ students scored $75$ marks, $12$ students scored $60$ marks, $8$ scored $40$ marks and $3$ scored $30$ marks. The mean of their score is (approximately) _________.

• A. $57$ marks
• B. $56$ marks
• C. $15$ marks
• D. $54$ marks

Answer 1

The correct option is A $57$ marks

Total marks obtained by all students :

$=10\times 75+12\times 60+8\times 40+3\times 30$

$=1880$

The total number of students:

$=10+12+8+3=33$

Average of their score:

$=\frac{1880}{33}$

$=56.96969697$

$=57$ (aproximately)