Question

67 80 64 ? 42 72 missing number series
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Answer 1

The given series:

67, 80, 64, ?, 42, 72

We have to find, the value of missing number (?) in the given series.

Solution:

The pattern follow:

Next number = Previous number + (Sum of digits) × 1, Previous number - (Sum of digits) × 2, Previous number + (Sum of digits) × 3, Previous number - (Sum of digits) × 4, .......

80 = 67 + (6 + 7) × 1

     = 67 + 13 = 80

64 = 80 - (8 + 0) × 2

     = 80 - 16 = 64

? = 64 + (6 + 4) × 3

⇒ ? = 64 + 10 × 3

⇒ ? = 94

42 = 94 - (9 + 4) × 4

    = 94 - 52 = 42

72 = 42 + (4 + 2) × 5

    = 42 + 30 = 72

∴ Missing number (?) = 94

Thus, the value of "missing number (?) is equal to 94".

Answer 2

Given:

67 80 64 ? 42 72

To find:

The missing number

Solution:

From given, we have the data as follows.

67 80 64 ? 42 72

We are asked to find the missing term of the given series.

80 = 67 + (6 + 7) × 1  = 67 + 13 = 80

64 = 80 - (8 + 0) × 2  = 80 - 16 = 64

? = 64 + (6 + 4) × 3  

⇒ ? = 64 + 10 × 3

⇒ ? = 94

42 = 94 - (9 + 4) × 4  = 94 - 52 = 42

72 = 42 + (4 + 2) × 5  = 42 + 30 = 72

Therefore, the missing term of the series is 94.