SSC CHSL 2024 PYQ — Question 70

The correct answer is option 1 i.e. 313.

a/b = $\frac{15}{8} + \left[\left\{\frac{4}{5} of \frac{5}{12} \div \left(1\frac{1}{15}\right)\right\} \times 1\,\frac{7}{12}\right]$

⇒  a/b = $\frac{15}{8} + \left[\left\{\frac{1}{3} \div \frac{16}{15}\right\} \times \frac{19}{12}\right]$

⇒  a/b = $\frac{15}{8} + \left[\left\{\frac{1}{3} \times \frac{15}{16}\right\} \times \frac{19}{12}\right]$

⇒  a/b = $\frac{15}{8} + \left[\frac{5}{16} \times \frac{19}{12}\right]$

⇒  a/b = $\frac{15}{8} + \left[\frac{5}{16} \times \frac{19}{12}\right]$

⇒ a/b = 15/8 + 95/192 = 455/192

a = 455 and b = 192

So, 4b - a = 4 × 192 - 455 = 768 - 455 = 313

Therefore, the value of 4b - a is 313.