Multiplication of two numbers that differ by 4

Maths Tricks , short cut tricks for maths to make calculation easy and fast

Multiplication of two numbers that differ by 4

If two numbers differ by 4, then their product is the square of the number in the middle (the average of the two numbers) minus 4.
Let me explain this rule by taking examples
22*26 = 24^2 - 4 = 572
98*102 = 100^2 - 4 = 9996

Example.

Understand the rule by 1 more example
148*152 = 150^2 - 4 = 22496

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