Multiply by 4 and 5

It is so easy with a simple trick we can easily multiply with 4 and 5 in your mind without paper or pen. How it can be? below given trick keep it always in your mind.

when want to multiply By 4

Just double the number and then double it again. (That is in maths aX2X2=aX4)

example: If you want to 250 multiply by 4, we do this way, doubling 250 will be 500. Again double the 500 is become 1000. (Mathematical tricks)

That is 250X4-1000. This can be done in your mind.

Same way

when you want to multiply By 5

Divide the number in 2 and then multiply it by 10.  (a/2X10=aX5)

Example: If you want to 100 multiply by 5, we do this way, divide the number 100 by 2 that is 50 and multiply with 10. Multiply by 10 again easy. Add one zero right side of the digit i.e. 50 adding a zero it will become 500. How easy!

Often this also can be done quickly in your mind.