If the first term of an arithmetic sequence is 5, and the common difference is 4, what is the 30th term?
Category: Math · Difficulty: expert
Hint: Use the formula for the n-th term of an arithmetic sequence.
Answer
121
Explanation
The n-th term is given by a + (n-1)d; here, 5 + (30-1)*4 = 121.
This is a expert math riddle — one of the harder riddles here. The answer is 121.
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