NECO 2023 · Paper 1 · Q2

Find the product of $10110_{\text{two}}$ and $11_{\text{two}}$ .

Worked solution (try it first)

Change to base ten: $10110_{\text{two}} = 16 + 4 + 2 = 22$ and $11_{\text{two}} = 3$ .
Multiply: $22 \times 3 = 66$ .
Change back: $66 = 64 + 2$ , so the product is $1000010_{\text{two}}$ , option A.