In an examination, there are three papers and a candidate has to get 35\% of the total to pass. In one paper, he gets 62 out of 150 and in the second 35 out of 150. How much must he get, out of 180, in the third paper to just qualify for a pass?
(a)60.5
(b)68
(c)70
(d)71
Answer
Answer (as printed): D
Explanation
Let the marks required be $x$. Then, $(62+35+x)=35 \%$ of ( $150+150+180$ ) $$\Leftrightarrow 97+x=\frac{35}{100} \times 480 \Leftrightarrow x=168-97=71 .$$
Explanation as extracted from the printed page; notation may be imperfect.