Question 5
An empty bus has 78 seats. One passenger boards at the 1st stop, 2 at the 2nd stop, 3 at the 3rd stop, and so on. At which stop will the bus have 12 seats left? Give the stop number.
Interpretation: every passenger takes one seat and nobody leaves the bus before the stop being considered.
Interpretation: every passenger takes one seat and nobody leaves the bus before the stop being considered.