10 EASY MATH TRICKS YOU PROBABLY DON'T KNOW















LETS DISCUSS SOME BASIS IDEAS IN MATHEMATICS

WHETHER YOU LOVE MATHS, OR DESPITE IT, THE FOLLOWING TRICKS CAN TURN YOU INTO A MATH WHIZ-OR AT LEAST WILL HELP TO SPEED UP SOME OF THE CALCULATIONS YOU NEED TO DO IN YOUR HEAD.

I'VE INCLUDED FIVE OF MY FAVORITES HERE........

QUICK SQUARE

 IF YOU NEED TO SQUARE A 2 DIGIT NUMBER ENDING IN 5, MULTIPLY THE FIRST DIGIT BY ITSELF PLUS 1, AND PUT 25 ON THE END. THAT'S ALL!

(25)^2=(2*(2+1))&25

2*3=6 & 25

625

MULTIPLYING BY 9

 TO MULTIPLY ANY NUMBER BETWEEN 1 AND 9 BY 9, HOLD BOTH HANDS IN FRONT OF UR FACE, WITH FINGERS EXTENDED. NOW DROP THE FINGER THAT CORRESPONDS TO THE NUMBER YOU R MULTIPLYING (FOR EXAMPLE, FOR 9*3, DROP UR THIRD FINGER). NOW COUNT THE FINGERS BEFORE THE DROPPED FINGER(IN THE CASE OF 9*3 IT IS 2)-THAT'S UR FIRST DIGIT. THEN, COUNT THE FINGERS AFTER (AGAIN IN THE CASE, IT'S 7). THE ANSWER IS 27.

DIVIDING BY 5

 TO DIVIDE A LARGE NUMBER BY 5, ALL YOU NEED TO DO IS MULTIPLE BY 2 AND MOVE THE DECIMAL POINT ONE SPACE TO THE LEFT..

400/5

 STEP 1; 400*2=800
STEP 2; MOVE THE DECIMAL LEFT; 80.0, OR JUST 80

1245/5

 STEP 1; 1245*2=2490
STEP 2; 249.0 OR 249

SUBTRACTING FROM 1000

 TO SUBTRACT A LARGE NUMBER FROM 1000,
SUBTRACT ALL THE NUMBER FROM 9 EXCEPT UNIT PLACE NUMBER,
THEN SUBTRACT THE UNIT PLACE NUMBER FROM 10....

1000-567=???

STEP 1; SUBTRACT 5 FROM 9 = 4
STEP 2; SUBTRACT 6 FROM 9 = 3
STEP 3; SUBTRACT 7 FROM 10 = 3

ANSWER IS 433

CALCULATE A TIP

 IF YOU NEED TO LEAVE A 20% TIP, HERE IS THE EASY WAY TO SOLVE. WORK OUT 10% (DIVIDE THE NUMBER BY 10), THEN ADD THAT NUMBER TO ITSELF AND YOU HAVE UR ANSWER....

20% OF RS 50

 (10% OF 50) + (10% OF 50)

5 + 5 = RS 10

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