Daily reminder that common core is attempting to make your kids hate math. Btw, I would also argue that the same thing is done in the programming world:

Haha. Math is easy kids! Just take your existing homework problems and turn them all into FIVE times the problems. Simple!

Combine this with that gawd awful Touch Math they're teaching kids these days and you'll have students that can process math like a potato!

Wow, that really looks awful
I'm glad I studied math long time ago...

that's... exactly how i do my mental math. sort of a difficult process to explain and make it sound useful? but yeah, whether i'm adding/subtracting/dividing/multiplying/squaring/rooting.... mentally i always start out finding an approximation that is close to the real answer, then using techniques like in that image i hone my way to the correct answer.

though, i would have gone 26 + 14 = 40, 17 - 14 = 3, 40 + 3 = 43.

=p