Binomial multiplication is easier.
1) In this problem, let's check and compare both ways and then state which one is easier.
2) As Binomials:
[tex]\begin{gathered} 18\times17=(20-2)(20-3)= \\ 400-60-40+6= \\ 400-60-34 \\ 306 \end{gathered}[/tex]Notice that the choice for subtracting from 20 is based on the fact that numbers ending in 0, like 10,20, etc. are easier to multiply.
2.2) Using the ordinary algorithm:
3) If we consider that multiplying numbers using binomial is faster when we consider "mental math" then the one with binomials is easier. Since the algorithm requires us to write it down.
