Method : 15's complement subtraction steps :
1. At first, find 15's complement of the B(subtrahend).
2. Then add it to the A(minuend).
3. If the final carry over of the sum is 1, then it is dropped and 1 is added to the result.
4. If there is no carry over, then 15's complement of the sum is the final result and it is negative.

---

1. Find Subtraction of 1B06 and 77C using 15's complement

Solution:

15's complement subtraction steps :

1. At first, find 15's complement of the B(subtrahend).
2. Then add it to the A(minuend).
3. If the final carry over of the sum is 1, then it is dropped and 1 is added to the result.
4. If there is no carry over, then 15's complement of the sum is the final result and it is negative.

Here A = 1B06, B = 077C.
Find A - B = ? using 15's complement
First find 15's complement of B = 077C


Step-1: 15's complement of 077C is obtained by subtracting each digit from F

	F	F	F	F
-	0	7	7	C
	F	8	8	3

---

Step-2: Now Add this F883 to 1B06

	1
	1	B	0	6
+	F	8	8	3
1	1	3	8	9

---

Step by step solution of 1B06 + F883 = 11389

Write the numbers, so that each digit lines up vertically

	1	B	0	6
+	F	8	8	3

Step-1 :
`=6_16+3_16`
`=6_10+3_10`
`=9_10`
`=9_16`
Write the 9 in the sum place

	1	B	0	6
+	F	8	8	3
				9

Step-2 :
`=0_16+8_16`
`=0_10+8_10`
`=8_10`
`=8_16`
Write the 8 in the sum place

	1	B	0	6
+	F	8	8	3
			8	9

Step-3 :
`=B_16+8_16`
`=11_10+8_10`
`=19_10`
`=16xx1+3`
`=13_16`
Write the 3 in the sum place and carry the 1 to the next carry place

	1
	1	B	0	6
+	F	8	8	3
		3	8	9

Step-4 :
`=1+1_16+F_16`
`=1+1_10+15_10`
`=17_10`
`=16xx1+1`
`=11_16`
Write the 11 in the sum place

	1
	1	B	0	6
+	F	8	8	3
1	1	3	8	9

---

The left most bit (1) of the result (11389) is called carry and add it to the rest part of the result (1389)

	1	3	8	9
+				1
	1	3	8	A

---

So answer is 138A

---

---