Answers

2015-07-04T10:19:55+08:00
142 is the seating capacity of the movie house with 40 rows ^^

Sol'n: Use the formula in adding arithmetic sequnces ----> Sn = first term + ( n-1)d

Sn = 25 + ( 40-1) 3
     = 25 + 39(3)
     = 142
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