Multiple choice

Directions: In the following number series, one number is wrong. Find out the wrong number. 8544, 1420, 280, 44, 18, 5

  1. 280

  2. 44

  3. 18

  4. 5
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The pattern is division: 8544/6 = 1424 (not 1420), 1424/5 = 284.8. Alternatively, checking the sequence: 5*3+3=18, 18*2+8=44, 44*6+16=280. The sequence is actually 8544, 1424, 284.8, 56.96. Given the options, 44 is the outlier in the provided sequence.

AI explanation

The series follows a pattern of dividing by a prime number and then adding a specific constant. Starting from 8544, we divide by 6 and add 4 to get 1428, but the series has 1420, so let us check another logic. The logic is subtracting 4 and dividing by 6: 8544 minus 4 is 8540, divided by 6 is not an integer. Let us try dividing by 6 and adding 4: 8544 divided by 6 is 1424, plus 4 is 1428, which is not 1420. Let us try dividing by 6 and subtracting 4: 8544 divided by 6 is 1424, minus 4 is 1420. For the next term, 1420 divided by 5 is 284, minus 4 is 280. Then 280 divided by 4 is 70, minus 4 is 66. The term 44 is wrong here because it should be 66. Continuing the pattern, 66 divided by 3 is 22, minus 4 is 18. Finally, 18 divided by 2 is 9, minus 4 is 5. The wrong number is 44.

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