secrets-of-mental-math-malestrom

90
Secrets of Mental Math
67
543657
3240
417
378
39
39
Answer: 67 54
Now try your hand at a problem with a three-digit answer:
9467 13
728
139467
9100
367
260
107
104
3
3
Answer: 728 13
Simplifying Division Problems
If by this point you’re suffering from brain strain, relax. As
promised, I want to share with you a couple of tricks for simplifying
certain mental division problems. These tricks are based
on the principle of dividing both parts of the problem by a common
factor. If both numbers in the problem are even numbers,
you can make the problem twice as easy by dividing each num-