Question

Find the missing number in the series: $3, 6, 18, 72, ?$

• A. 144
• B. 216
• C. 288
• D. 360

Hint:

When working with sequences, carefully identify if the pattern is additive, multiplicative, or a combination. Check differences or ratios between terms.

Answer 1

The Correct Option is D

Step 1: Examine the ratio between consecutive terms:
\[ \frac{6}{3} = 2, \quad \frac{18}{6} = 3, \quad \frac{72}{18} = 4. \] Step 2: Notice that the multiplier increases by 1 with each step: from 2 to 3 to 4.
Step 3: Predict the next multiplier by continuing this pattern: \(4 + 1 = 5\).
Step 4: Multiply the last known term by the next multiplier:
\[ 72 \times 5 = 360. \] Therefore, the missing number in the series is 360.