Question

Durba got 70% marks in an exam. He obtained 20 out of 25 marks in another exam. If his total score is 78% then what were the maximum marks of the first exam? (a) 7.6 (b) 6.25 (c) 7.25
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Answer 1

Total Marks in Exam = X

Marks of A = 60% of Total Marks

= 60X/100

Marks of B = 25% of Total Marks

= 25X/100

According to question;

Passing marks of A and B are same.

Marks of A - 844 = Marks of B + 63

60X/100 - 84 = 25X/100 + 63

60X/100 - 25X/100 = 63 + 84

35X/100 = 147

X = (147 × 100)/35

X = 420

Answer 2

Given:

Durba got 70% marks in an exam. He obtained 20 out of 25 marks in another exam

To Find:

If his total score is 78% then what were the maximum marks of the first exam? (a) 7.6 (b) 6.25 (c) 7.25

Solution:

Let the total score of the 1st exam be x then the score obtained will be 0.7x as it is mentioned that 70% is scored and in the 2nd exam, he scores 20 out of 25.

So the total score obtained will be (20+0.7x)

and the total score will be (25+x)

Now it is said that the total score obtained is 78% of the total maximum marks, now we can express it as,

$78\% of(25+x)=(20+0.7x)\\19.5+0.78x=20+0.7x\\0.08x=0.5\\x=6.25$

So the maximum score in the 1st exam is 6.25 and the score obtained will be 0.7*6.25=4.375

Hence, the correct option is (b).