NIMCET 2025 — Computer PYQ
NIMCET | Computer | 2025What is the equivalent decimal value of the unsigned binary number 10101.10101?
Choose the correct answer:
- A.
51.125
- B.
125.25
- C.
25.375
- D.
21.65625
(Correct Answer)
21.65625
Explanation
1. Integer Part (10101)2:
Calculate from right to left starting from 20:
(1×24)+(0×23)+(1×22)+(0×21)+(1×20)
16+0+4+0+1=21
2. Fractional Part (.10101)2:
Calculate from left to right starting from 2−1:
(1×2−1)+(0×2−2)+(1×2−3)+(0×2−4)+(1×2−5)
0.5+0+0.125+0+0.03125
0.5+0.125+0.03125=0.65625
3. Combine both parts:
21+0.65625=21.65625
Final Equation
(10101.10101)2=(21)10+(21+81+321)10
(10101.10101)2=21+0.5+0.125+0.03125
(10101.10101)2=(21.65625)10
Explanation
1. Integer Part (10101)2:
Calculate from right to left starting from 20:
(1×24)+(0×23)+(1×22)+(0×21)+(1×20)
16+0+4+0+1=21
2. Fractional Part (.10101)2:
Calculate from left to right starting from 2−1:
(1×2−1)+(0×2−2)+(1×2−3)+(0×2−4)+(1×2−5)
0.5+0+0.125+0+0.03125
0.5+0.125+0.03125=0.65625
3. Combine both parts:
21+0.65625=21.65625
Final Equation
(10101.10101)2=(21)10+(21+81+321)10
(10101.10101)2=21+0.5+0.125+0.03125
(10101.10101)2=(21.65625)10

