Section 6: Functions 90
Adding and Subtracting Time and Angles
To add or subtract decimal hours, merely key in the numbers from the decimal hours and press  +  or  –  . To add hours, minutes, seconds, use the HMS+ (add hours, minutes, seconds) or HMS– (subtract hours, minutes, seconds) function. Both of these functions are executed using XEQ or by assigning them to a key for execution in USER mode.
Likewise, angles specified in degrees, minutes, seconds are added and subtracted using the HMS+ and HMS– functions.
Assign HMS+ and HMS– to the LOG and 10x keys, respectively, for execution in USER mode.
Keystrokes Display
g ASN
 ASN _

ALPHA
HMS g +
ALPHA
 ASN HMS+ _

LOG
 ASN HMS+ 14

 0

g ASN
 ASN _

ALPHA
HMS g
ALPHA
 ASN HMS– _

g 10x
 ASN HMS– –14

 0

USER
 0

Example: Find the sum of 45 hours, 10 minutes, 50.76 seconds and 24 hours, 49 minutes, 10.95 seconds, then subtract 7 hours, 23 minutes, 11 seconds from that result.
Keystrokes Display
45.105076
 45.105076 _

ENTER
 45.1051

24.491095
 24.491095 _

HMS+ ( LOG )
 70.0002

7.2311
 7.2311 _

g HMS– ( 10x )
 62.3651