To find the pattern first find the differences between consecutive terms:

• 320 - 254 = 66

• 254 - 200 = 54

• 200 - 155 = 45

• 155 - 122 = 33

• 122 - 100 = 22

• 100 - 89 = 11

The Diiference should be 11,22,33,44,55,66

• 320 - 66 = 254

• 254 - 55 = 199

• 199 - 44 = 155

• 155 - 33 = 122

• 122 - 22 = 100

• 100 - 11 = 89

Hence 200 is the wrong term and in place of 200 there should be 199