Binary and decimal numbers
Answers are for parents and teachers.
1
Turn (10011010)₂ into decimal.
128 + 16 + 8 + 2 = 154.
2
Turn 70 into binary by repeated division by 2 and show the remainders.
The remainders from top to bottom are 0, 1, 1, 0, 0, 0, 1; read from the bottom, the answer is 1000110 (64 + 4 + 2 = 70).
3
Convert 51 to binary by subtracting place values, then check back.
32 fits, 16 fits, 8 and 4 do not, 2 fits, 1 fits: 110011. Check: 32 + 16 + 2 + 1 = 51.
4
Explain what LSB and MSB mean and name them in 110011.
LSB is the bit on the right, worth 1 (here 1); MSB is the bit on the left, with the largest place value (here 1).
5
A student says (10111)₂ = 16 + 8 + 2 + 1 = 27. Find the mistake and give the right value.
The second 1 stands under the place worth 4, not 8. The right value is 16 + 4 + 2 + 1 = 23.