Also if you are trying to find the answers to choose it's
A. She subtracted instead of adding the times.
B. She subtracted the end time from the start time.
C. She did not regroup 1 hour for 60 minutes to subtract the minutes.
D. She did not account for a.m. and p.m. in the start and end times.
E. She switched the hours and minutes in both the start and end times.
School started at 8:05 a.m. and ended at 2:40 p.m. The work below shows Erica’s calculation of the length of the school day.
7hr 65
8 hr 5 min -
2hr 40 min
---------------
5hr 25 minutes
Which two errors did Erica make?
4 answers
Choose two.
Who knows how she got that
Maybe that cumbersome method of pm and am got in the way.
2:40 pm -----> 14:40
8:05 am -----> 8:05
14:40 - 8:05 = 6:35
On you calculator, look for a key similar to D°M'S
This will allow you to do addition and subtraction
of units of time, D would be hours, M is minutes and S is seconds
The original intent was to do operations of units and angles, but
since units of time of hours, minutes, seconds are structured in the
same way as angles in degrees, minutes and seconds, it serves
well for both units.
Maybe that cumbersome method of pm and am got in the way.
2:40 pm -----> 14:40
8:05 am -----> 8:05
14:40 - 8:05 = 6:35
On you calculator, look for a key similar to D°M'S
This will allow you to do addition and subtraction
of units of time, D would be hours, M is minutes and S is seconds
The original intent was to do operations of units and angles, but
since units of time of hours, minutes, seconds are structured in the
same way as angles in degrees, minutes and seconds, it serves
well for both units.
1.b, d
3 answers