Q115 of 140 Page 196

In an examination, there are three papers each of 100 marks. A candidate obtained 53 marks in the first and 75 marks in the second paper. How many marks must the candidate obtain in the third paper to get an overall of 70 per cent marks?

⇒ Let x be the marks of candidate in thirs paper


⇒ total marks secured in all three papers = 53 + 75 + x


⇒ Total marks of three papers = 100 + 100 + 100 = 300


⇒ Percentage of marks = × 100%


= × 100%


⇒ Overall 70% of marks obtained


⇒ × 100 = 70


⇒ = 70


⇒ 128 + x = 210


⇒ x = 210 – 128


⇒ x = 82


Hence, 82 marks must be secured to get overall of 70% marks


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