Multiple choice

Directions: Find the next term of the series: 9, 29, 69, 129, 209, __

  1. 303

  2. 309

  3. 319

  4. 308

  5. 329
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The differences are: 29-9=20, 69-29=40, 129-69=60, 209-129=80. The differences are in an arithmetic progression (20, 40, 60, 80). The next difference should be 100. Next term = 209 + 100 = 309.

AI explanation

The differences between the consecutive terms are multiples of 10, increasing by 10 each time (20, 40, 60, 80, and 100). So, 9 plus 20 is 29, 29 plus 40 is 69, 69 plus 60 is 129, and 129 plus 80 is 209. Adding the final difference of 100 to 209 gives 309.

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