Question

Question: In an examination, a pupil's average marks were 70 per paper. If he had obtained 25 more marks for his maths paper and 7 more marks for his science paper, his average per paper would have been 78. How many papers were there in the examination ? O 11 05 4 6​

Answer 1

Answer:

4 papers in examination.

Step-by-step explanation:

given average marks x` = 70

and added marks are 25 and 7 which are equal to 32

average = total marks (say y) by total papers (say z) = 70

new average = y+32/z =78

assume that there are 4 papers then substitute 4 in z

y+32/4=78

y+32=78×4

y+32=312

y=312-32

y=280=total marks

if you divide 280(y) with 4 (z) then you'll get previous average 70