In an arithmetic sequence, the 7th term is 30, and the 11th term is 60. What is the 21st term of this sequence?
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<|im_start|>user
In an arithmetic sequence, the 7th term is 30, and the 11th term is 60. What is the 21st term of this sequence?
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In an arithmetic sequence, the 7th term is 30, and the 11th term is 60. What is the 21st term of this sequence?
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