Look at this series: 1.5, 2.3, 3.1, 3.9, ... What number should come next?

Given data

• Series terms: 1.5, 2.3, 3.1, 3.9, ...

Concept/Approach
Check consecutive differences to spot a constant step.

Step-by-step calculation
2.3 − 1.5 = 0.83.1 − 2.3 = 0.83.9 − 3.1 = 0.8Next term = 3.9 + 0.8 = 4.7

Verification/Alternative
A simple arithmetic progression with common difference 0.8 fits all terms.

Common pitfalls

• Assuming alternating steps (they are constant here).

Final Answer
4.7