An employee pays Rs. 26 for each day a worker and forfeits Rs. 7 for each day he idle. At the end of 56 days, if the worker got Rs. 829, for how many days did the worker remain idle?

His Per day pay = Rs. 26
Total pay employee got = Rs. 829
Total pay he gets if he did not remain idle a single day,
= 26 × 56 = Rs.1456
He Forfeits or fined = 1456 - 829 = Rs. 627
Per day he Forfeits Rs. 7 Means per idle day he loses = 26 + 7 = Rs. 33
So, Total idle days = $$\frac{{627}}{{33}}$$ = 19 days

Alternatively,
Let he works for X days and remain idle for (56 - X)
Now, According to question,
X × 26 - 7 × (56 - X) = 829
26X + 7X - 392 = 829
33X = 829 + 392 = 1221
X = 37 days
Number of days remain idle = 56 -37 =19 days