Question

Decimal number 10 is equal to binary number a. 1110 b. 1010 c. 1001 d. 1000

Answer 1

Let's check each and every option. As the number is small we can easily find the solution using trial and error method.
Option a) 1110
From left we have to represent as 0 1 2 3...
Ie 1 1 1 0
3 2 1 0
Then take two power the number and add
$1 \times {2}^{3} + 1 \times {2}^{2} + 1 \times {2}^{1} + 1 \times {2}^{0}$
Answer=14
Option b) 1010
Doing as above
$1 \times {2}^{3} + 0 \times {2}^{2} + 1 \times {2}^{1} + 0 \times {2}^{0}$
Answer=10
Option c) 1001
$1 \times {2}^{3} + 0 \times {2}^{2} + 0 \times {2}^{1} + 1 \times {2}^{0}$
Answer=9
Option d) 1000
$1 \times {2}^{3} + 0 \times {2}^{2} + 0 \times {2}^{1} + 0 \times {2}^{0}$
Answer=8.
From the above analysis. We can deduce that option b) 1010 is the correct representation of 10 in binary form.