The problem is a geometric sequence.
The sequence in the problem:
1, 2, 4, 8, 16
To find the total text messages sent, solve for the geometric sequence.
where r ≠ 1
a₁ = first sequence, 1
r = common ratio, 2
n = number of terms, 5 (number of rounds)S₅ = 31ANSWER: A total of 31 text messages were sent.
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