Answer:
155 miles
Explanation:
The sum of n terms of an arithmetic series is given by the formula ...
Sn = (2·a1 +d(n -1))(n/2)
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The number of miles Ryan ran in July is described by the arithmetic series ...
0.5 +0.8 +1.1 +... (a total of 31 terms)
The first term is a1=0.5, and the common difference is d=0.3.
The total number of miles Ryan ran in July is ...
S31 = (2(0.5) +0.3(31 -1))(31/2) = (1 +9)(31/2) = 155
Ryan ran 155 miles in July.