please give me some maths tricks with explanation
Answers
TRICK NO. 1
Think of a number.
Multiply it by 3.
Add 6.
Divide this number by 3.
Subtract the number from Step 1 from the answer in Step 4.
The answer is 2.
TRICK NO. 2
This is a quick way to multiply two-digit numbers by 11 in your head.
Separate the two digits in your mind.
Add the two digits together.
Place the number from Step 2 between the two digits. If the number from Step 2 is greater than 9, put the one's digit in the space and carry the ten's digit.
Examples: 72 x 11 = 792.
The 11 Rule
This is a quick way to multiply two-digit numbers by 11 in your head.
Separate the two digits in your mind.
Add the two digits together.
Place the number from Step 2 between the two digits. If the number from Step 2 is greater than 9, put the one's digit in the space and carry the ten's digit.
Examples: 72 x 11 = 792.
57 x 11 = 5 _ 7, but 5 + 7 = 12, so put 2 in the space and add the 1 to the 5 to get 627
06
of 10
Memorizing Pi
To remember the first seven digits of pi, count the number of letters in each word of the sentence:
"How I wish I could calculate pi."
This becomes 3.141592.
hope it helps