RRB Paramedical Staff Nurse Model Paper 7

A labourer was appointed by a contractor on the condition that he would be paid Rs. 75 for each day of his work but would be fined at the rate of Rs.
15 per day for his absence, apart from losing his wages. After 20 days, the contractor paid the labourer Rs. 1140. The number of days the labourer abstained from work was