Grade 6 problem

Patterns · Grade 6

The first row of an auditorium has 11 seats. Each following row has 7 more seats than the previous row. How many seats are in the twentieth row?

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  1. There are 19 transitions between the first and twentieth rows.
  2. Calculate 11 + 19 × 7.
Show the answer and solution

Answer: 144

There are 19 transitions from the first row to the twentieth, each adding 7 seats. Thus, 11 + 19 × 7 = 144 seats.

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