For this case we have the following sequence: 0.8 3.2 12.8 51.2 This sequence can be written as: 0.8 = 0.2 * 4 = 0.2 * 4 ^ 1 3.2 = 0.2 * 16 = 0.2 * 4 ^ 2 12.8 = 0.2 * 64 = 0.2 * 4 ^ 3 51.2 = 0.2 * 256 = 0.2 * 4 ^ 4 Therefore, we have that the generic expression for this case is: an = 0.2 * 4 ^ n Then, the next number is then: a5 = 0.2 * 4 ^ 5 = 0.2 * 1024 = 204.8 answer the next number in the pattern is 204.8