Page 50 - ComputerScience_Class_11

19. Subtract the given hexadecimal numbers (9A78.25) - (FAD.50) using:
16
16
a. Borrow method
b. 15’s complement method
c. 16’s complement method
Ans. a. +16 +16 +16 +16

9 8 A 9 7 6 8 7 . 2 5
- F A D . 5 0
8 A C A . D 5
(8ACA.D5) 16
b. 15’s complement of 0FAD.50 is F052.AF +1 +1
Adding 9A78.25 and F052.AF, we get 9 A 7 8 . 2 5
(8ACA.D5) + F 0 5 2 . A F
16
1 8 A C A . D 4
1
8 A C A . D 5

c. 15’s complement of 0FAD.50 is F052.AF +1
16’s complement of F052.AF is F052.B0 9 A 7 8 . 2 5
Adding 9A78.25 and F052.B0, we get + F 0 5 2 . B 0
Ignoring MSB 1, we get 1 8 A C A . D 5
(8ACA.D5) 16

20. Subtract (1B7) - (8D27) using:
16
16
a. 15’s complement method
b. 16’s complement method
Ans. a. 15’s complement of 8D27 is 72D8 +1
Adding 1B7 and 72D8, we get 1 B 7
15’s complement of 748F is 8B70 + 7 2 D 8
(-8B70) 16 7 4 8 F
b. 15’s complement of 8D27 is 72D8 +1 +1
16’s complement of 72D8 is 72D9 1 B 7
Adding 1B7 and 72D9, we get 7490 + 7 2 D 9
15’s complement of 7490 is 8B6F 7 4 9 0
16’s complement of 8B6F is 8B70
(-8B70) 16
21. Perform the following Octal multiplication:
a. 52 × 33 b. 170 × 44
8 8 8 8
Ans. 5 2 1 7 0
x 3 3 x 4 4
+1 +3
7 6 4 4 0
+1 +3
7 6 x 4 4 0 x
2 1 5 6 1 0 3 4 0

2156 8 10340 8

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