Is this SAT Math question wrong??

Test Preparation
1

<p>a, 3a, ...</p>

<p>The first term in the sequence above is a, and each term after the first is 3 times the preceding term. If the sum of the first 5 terms is 605, what is the value of a.</p>

<p>I got 5 as the answer, but the new blue book says 6. When a=5, the sum is 605, but when a=6 the sum is 726. Am i doing something wrong.</p>

2

<p>I think that was a mistake in the book. There should have been a yellow piece of paper in the front cover with the corrected mistakes.</p>