Let Latika takes a fixed charge for the first two day is Rs x and additional charge for each day thereafter is Rs y.

Now by first condition.

Latika paid Rs 22 for a book kept for six days i.e., for first two days as Rs x and remaining Rs 4y.

x + 4y = 22 …(i)

and by second condition,

Anand paid Rs 16 for a book kept for four days i.e., for first two days as x’ and remaining Rs 2y.

x + 2y = 16 …(ii)

Now, subtracting Eq. (ii) from Eq. (i), we get

2y = 6

y = 3

On putting the value of y in Eq. (ii), we get

x + 2(3) = 16

x = 10

Hence, the fixed charge = Rs 10

and the charge for each extra day Rs 3.