Multiplication on a diagonal grid

It's been a while since we've done any kind of math by hand, so please forgive our ignorance of this exercise being taught in some elementary schools: the diagonal multiplication grid. We agree with Signal vs. Noise, which finds the grid interesting but has no idea about its effectiveness over old-fashioned methods--let alone a calculator.

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Top 5: Cars with best resale value

Brian Cooley runs down the top five US automobiles with the best resale value in 2015, five years after original sale.

by Brian Cooley