Sixth-grade Math Minutes Answer Key - myilibrary.org 180 Days Of Math For Sixth Grade Day 150 Answers Key. Answer: The next number in the sequence is 326, 276, 226, 176. Explanation: The given sequence is 326, 276, 226, The difference between the first and second numbers is 50. 326 - 276 = 50. The difference between the second and third number is 10. 276 - 226 = 10.