The display of a 24-hour digital clock shows hours and minutes in the format XX:XX. For what fraction of a day is at least one 0 displayed on this clock?
+14915 The display of a 24-hour digital clock shows hours and minutes in the format XX:XX. For what fraction of a day is at least one 0 displayed on this clock?
Hello Guest!
01h to 10h and 20h 11 x 60min \(=660\ min\)
11h to 19h and 21h to 24h 13 x (12 + 9) \(=\underline{273\ min}\)
\(=933\ min\)
24h x 60min/h \(= 1440\ min\)
\(\frac{933\ min}{1440\ min}=0.648\)
A zero is displayed on 0.648 of a day.
!
+36916 Hmmmm...I get a slightly different answer
Each of the hours 00-10 and 20 have a zero the entire 60 minutes (at 24:00 the clock turns to 00:00)
12 x 60
There are 12 hours (11 -19 and 21,22,23) left that have zeroes for minutes 00 - 10 and :20 :30 :40 :50
12 x 15 (Note: there is no 24:00 ..... at 23:59:59 the next time is 00:00:00)
there are 24 x 60 minutes per day
(12*60 + 12*15) / (24*60) * 100% = 62.5 % as 'Guest ' found
