We have been given the number of customers that ate in three weeks.
Number of customers in 1st week = 115
Number of customers in 2nd week = 132
Number of customers in 3rd week = 149
If we collect all of them then we get sequence {115, 132, 149}
Notice that common difference between consecutive terms is constant which is 17
132-115=17
149-132=17
So that means, above sequence is arithmetic and hence we can use properties of sequence to find the next number in that sequence which can be easily obtained by adding 17 to the last number
149+17 = 166
Hence final answer is 166.