Explain above questions ---Sandy's watch reads 1850.
What is the time one quarter of an hour later, in 12-hour format?
A 6:35 am
B 7:05 am
C 6:35 pm
D 6:45 pm
E 7:05 pm
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Sandy's watch reads 1850, which is 18 hours and 50 minutes in 24-hour format. We need to find the time one quarter of an hour later in 12-hour format. One quarter of an hour equals 15 minutes. Adding 15 minutes to 18:50 gives us 18 hours and 65 minutes, which converts to 19 hours and 5 minutes. To convert from 24-hour format to 12-hour format, we subtract 12 from hours greater than 12. So 19 minus 12 equals 7. Therefore, the time one quarter of an hour later is 7:05 PM. The answer is E.
Let's analyze the time calculation step by step. Starting at 18:50, we add 15 minutes, which is one quarter of an hour. This gives us 18 hours and 65 minutes. Since 65 minutes exceeds 60, we convert it to 1 hour and 5 minutes. Adding this to 18 hours gives us 19:05. To convert from 24-hour format to 12-hour format, we first determine if it's AM or PM. Since 19:05 is after 12:00, it's PM. Then we subtract 12 from the hours: 19 minus 12 equals 7. The minutes remain the same. So 19:05 in 24-hour format becomes 7:05 PM in 12-hour format. Looking at our options, the correct answer is E: 7:05 PM.
Let's analyze why E, 7:05 PM, is the correct answer by examining each option. Option A, 6:35 AM, has both the wrong time and the wrong period. Option B, 7:05 AM, has the correct time but the wrong period - it should be PM, not AM. Option C, 6:35 PM, has the correct period but the wrong time - it's not 6:35. Option D, 6:45 PM, has the correct period but the wrong time - it only adds 10 minutes instead of 15. Option E, 7:05 PM, is correct because it properly adds 15 minutes to 18:50, giving us 19:05, which is 7:05 PM in 12-hour format. This matches our calculation: starting with 18:50 (6:50 PM), adding 15 minutes gives us 19:05 (7:05 PM).
Let's explore time format conversion methods. The 24-hour format, also known as military time, uses hours from 00 to 23, with no AM or PM designation. For example, 1850 means 18 hours and 50 minutes, or 6:50 PM in 12-hour format. To convert from 24-hour to 12-hour format, we follow these rules: For hours 0 to 11, we keep the hour and add AM. For hour 12, we use 12 and add PM. For hours 13 to 23, we subtract 12 and add PM. And for hour 0, we use 12 AM. Looking at our conversion chart, we can see that 18:50 in 24-hour format is 6:50 PM in 12-hour format. When we add 15 minutes, we get 19:05, which converts to 7:05 PM. This confirms our answer choice E is correct.
Let's summarize what we've learned. Sandy's watch reads 1850, which is 18 hours and 50 minutes in 24-hour format, equivalent to 6:50 PM in 12-hour format. We needed to find the time one quarter of an hour later. One quarter of an hour equals 15 minutes. Adding 15 minutes to 18:50 gives us 19:05. To convert 19:05 from 24-hour format to 12-hour format, we subtract 12 from the hours since it's after noon: 19 minus 12 equals 7. So the time is 7:05 PM. Therefore, the correct answer is option E: 7:05 PM. This problem tested our understanding of time formats and basic time calculations.