Let, number of double rooms and single rooms are d and s.
d + s = 26 ....1 )
Hotel rents double rooms at $34 per day and single rooms at $27 per day.
34d + 27s = 807 ....2)
Solving equation 1 and 2, we get :
34( 26 - s ) + 27s = 807
884 - 34s + 27s = 807
7s = 77
s = 11
And d = 26 - 11 = 15
Therefore, number of double rooms and single rooms are 15 and 11.
Hence, this is the required solution.
