Number series – extend the pattern by two terms. Sequence: 10, 20, 25, 35, 40, 50, 55, ____ , ____
Verbal Reasoning
Number Series
Difficulty: Easy
Choose an option
-
A70 65
-
B60 70
-
C60 75
-
D60 65
-
E65 70
Answer
Correct Answer: 65 70
Explanation
Introduction / Context:The sequence alternates between adding 10 and adding 5. Recognizing alternating fixed increments is a common test of series reasoning.
Given Data / Assumptions:
- Given: 10, 20, 25, 35, 40, 50, 55
- Find the next two terms.
Concept / Approach:Identify the repeating operation: +10, then +5, and so on.
Step-by-Step Solution:
10 → 20: +1020 → 25: +525 → 35: +1035 → 40: +540 → 50: +1050 → 55: +5Next step should be +10: 55 + 10 = 65Next step after that should be +5: 65 + 5 = 70Verification / Alternative check:The +10, +5 pattern is consistent from the start; applying it forward yields 65, then 70.
Why Other Options Are Wrong:
- 60 70 / 60 75 / 60 65: Insert 60 incorrectly; 55 + 10 is 65, not 60.
- 70 65: Reverses the order and breaks the alternating rule.
Common Pitfalls:Mixing the order of +10 and +5 or starting the alternation from the wrong point. Follow the step-by-step increments carefully.
Final Answer:65 70