Answer:
(a) an = 18 +3(n -1)
(b) row 35
Step-by-step explanation:
(a) The general term (an) of an arithmetic sequence can be expressed in terms of the first term (a1) and the common difference (d) as ...
an = a1 +d(n -1)
The given sequence has a1 = 18 and d = 3, so the explicit formula is ...
an = 18 + 3(n -1)
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(b) We want to find n such that an = 120.
120 = 18 + 3(n -1)
40 = 6 + n - 1 . . . . . . . divide by 3
35 = n . . . . . . . . . . . . . subtract 5
Row 35 has 120 seats.
The answer to your problem is 2
David will finish first, because if you divide Brad's miles by 2 to his miles in a 1/4 of an hour are 5.95 miles. This means David went 6.2 miles in the same time that Brad went 5.95. Therefore, David will finish first.
Check the picture below.
thus
as far as 5, is correct, however
