EXPLANATION :
The cost of a 12 nights camp accommodation is 6720.
We need to divide the cost by 12 to get the cost per day.
Now, we are asked to find the cost of 7 nights and 4 nights.
We just need to multiply the daily rate by the number of nights.
a. 7 nights :
7 x 560 = 3920
b. 4 nights :
4 x 560 = 2240
ANSWER :
a. 3920
b. 2240