Question

George found that he blinked 85 times in 15 minutes. At this rate, how many seconds passed during 51 blinks

Answer 1

85 / 5 = 15
15 / 5 = 3

15 / 3 = 5
3 / 3 = 1

Therefore, he blinks 5 times a minute.

60 / 5 = 12
5 / 5 = 1

Therefore, he blinks once every 12 seconds.

51 / 1 = 51

51
X 12
= 102
+ 510
= 612

Therefore, 612 seconds passed during 51 blinks.