In a regular week, there are 5 working days and for each day, the working hours are 8. A man gets Rs. 2.40 per hour for regular work and Rs. 3.20 per hours for overtime. If he earns Rs. 432 in 4 weeks, then how many hours does he work for?

Correct Answer: (B) 175

In 4 weeks, regular hours total $4$$\times$ 5 $\times$ 8 = 160 $\text{ hours}$. Regular earnings are $160$$\times$ 2.40 = $\text{Rs. }$ 384. The remaining earnings from overtime are $432 - 384 =$$\text{Rs. }$ 48. At an overtime rate of Rs. 3.20 per hour, overtime hours worked are $48 / 3.20 = 15$$\text{ hours}$. The total hours worked are $160 + 15 = 175$$\text{ hours}$.