Two airport shuttle buses arrive at a subway station at 7: 30 am if one airport shuttle bus arrives every 8 minutes and the other airport shuttle bus arrives every 10 minutes, what is the next time they will arrive at the subway together?

see explanation

step-by-step explanation:

since the sequence is geometric there is a common ratio r between consecutive terms, that is

r = 4 ÷ - 2 = - 2

r = - 8 ÷ 4 = - 2

r = 16 ÷ 8 = - 2

the next term - 13 must be incorrect as it should be - 32 for the sequence to be geometric.

the first 4 terms are therefore geometric with common ratio r = - 2

b. 153 students do not participate in sports and seventy-five 12th graders were surveyed