In each blank below a single digit is inserted such that the following six three-digit numbers, in this order, form an arithmetic sequence: 1__,__9,2_2,_6_,2__,_3_ What is the value of the next number in the sequence?
The last digit of the common difference is 3
A little trial and error produces......
232 + 33 = 265
265 + 33 = 298
298 + 33 = 331
232 - 33 = 199
199 - 33 = 166
So...the next number is
331 + 33 =
364