Ce diaporama a bien été signalé.
Le téléchargement de votre SlideShare est en cours. ×

# Amazing Math Tips & Tricks

Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Publicité
Prochain SlideShare
Math tricks
Chargement dans…3
×

## Consultez-les par la suite

1 sur 33 Publicité

# Amazing Math Tips & Tricks

Simple math tips & tricks for multiplication and divisibility check.

Simple math tips & tricks for multiplication and divisibility check.

Publicité
Publicité

## Plus De Contenu Connexe

Publicité

Publicité

### Amazing Math Tips & Tricks

1. 1. Welcome to the World of MATHEMA-TRICKS Minhas Kamal
2. 2. Today we will learn some cool math tricks. So that, we can use more our brain and less our calculator. 1
3. 3. Square a two digit number ending in 5 For example: 152, 452, 852 2
4. 4. Square a two digit number ending in 5 Lets consider the number 35. 1. We take the first digit and multiply it with it’s next number. 3 5 3 * 4 = 12 2. Then simply put 25 after it. 1 2 2 5 So, 352 = 1225 3
5. 5. Square a two digit number ending in 5 Here is another example: Step-1: 9 5 9 * 10 = 90 Setp-2: 9 0 2 5 So, 952 = 9025 4
6. 6. Multiply any number by 4 Simply double the number two times. 5
7. 7. Multiply any number by 4 Take the number 63 63*4 = 63*(2*2) = (63*2)*2 = 126*2 = 252 Lets try another number 753 double of 753 = 1506 double of 1506 = 3012 So, 753 * 4 = 3012 6
8. 8. Multiply any number by 5 Simply half the number & multiply it by 10. 7
9. 9. Multiply any number by 5 Take the number 86 86*5 = 86*(10/2) = (86/2)*10 = 43*10 = 430 Lets try another number 495 half of 495 = 247.5 247.5 * 10 = 2475 So, 495 * 4 = 2475 8
10. 10. Multiply any number by 15 Multiplication by 10 + Multiplication by 5. 9
11. 11. Multiply any number by 15 Take the number 84 84*10 = 840 84*5 = (84/2)*10 = 42*10 = 420 84*15 = 840 + 420 = 1260 Lets try another number 495 495*15 = 495*10 + 495*5 = 4950 + (495/2) * 10 = 4950 + 2475 = 7425 10
12. 12. Multiply any number by 11 x y z x y + z zx + yxyz * 11 = 11
13. 13. Multiply any number by 11 Take the number 263 Lets try another number 485 2 6 3 2 9 38263 * 11 = 4 8 5 5 3 53263 * 11 = 11 12
14. 14. Multiply two numbers between 10 and 20 For example: 15*17, 19*13 13
15. 15. Multiply two numbers between 10 and 20 Lets consider the number 12*14. 1. Add the first number with the other number’s second digit. 1 2 + 1 4 1 6 2. Place a 0(zero) after it. 1 6 1 6 0 14
16. 16. Multiply two numbers between 10 and 20 3. Multiply the second digits of the two numbers. 1 4 * 1 2 8 4. Add this number with the step-2 result. 1 6 0 + 8 1 6 8 So, 12*14 = 168 15
17. 17. Multiply two numbers between 10 and 20 Here is another example: 17*13 Step-1: 17 + 3 = 20 Setp-2: 20 200 Step-3: 7 * 3 = 21 Step-4: 200 + 21 = 221 So, 17*13 = 221 16
18. 18. Divisibility Check For example: is 7403 is divisible by 11 ? 17
19. 19. Divisibility Check (for 2, 3) A number is divisible by 2 if its last digit is 0, 2, 4, 6 or 8. For example: 12, 5394, 993120. A number is divisible by 3 if sum of its digits is divisible by 3. For example: 72 is divisible by 3 as 7+2=9 which is divisible by 3. Another example: 57381, 5+7+3+8+1=24; 24 is divisible by 3. So 57381 is also divisible by 3. 18
20. 20. Divisibility Check (for 5, 7) A number is divisible by 5 if its last digit is 0 or 5. For example: 100, 3795, 698170. For 7, separate & double the last digit of the number. Then subtract it from the rest. Take: 91. 91 9 1 9 - (1*2) 7 Now, if the number is 0 or divisible by 7, then the original number is also divisible by 7. 19
21. 21. Divisibility Check (for 7) If the number is big then continue the process as many time as needed. Lets take 3752. 3752 375 – 2*2 371 37 – 1*2 35 Now, 35 is divisible by 7. So, 3752 is also divisible by 7. Youmayhavegoneevenfurther, 35 3-5*2 -7 ; whichisalsodivisibleby7. 20
22. 22. Divisibility Check (for 11) For 11, add and subtract digits in an alternative pattern (like- 1st digit - 2nd digit + 3rd digit …). Take:8525 8-5+2-5=0 So,itisdivisibleby11. Take:392755 3-9+2-7+5-5=-11 Alsodivisibleby11 21
23. 23. Divisibility Check (for 13) For 13, add 4 times of the last digit to the rest of the number. Take: 351 351 35+1*4 39 Itisdivisibleby13. Letstryanother:754 754 75+4*4 75+16 91 9+1*4 13 So, you know. 22
24. 24. So we have leant a lot of math tricks today. Practice to make them perfect for you. 23
25. 25. There is one math trick only for YOU! 24
26. 26. Lets see if you can do it right! 25
27. 27. Add these numbers one after another- 1000 20 26
28. 28. Add these numbers one after another- 1000 20 1000 30 26
29. 29. Add these numbers one after another- 1000 20 1000 30 1000 40 26
30. 30. Add these numbers one after another- 1000 20 1000 30 1000 40 1000 10 26
31. 31. Add these numbers one after another- 1000 20 1000 30 1000 40 1000 10 5000 ??? 26
32. 32. Add these numbers one after another- 1000 20 1000 30 1000 40 1000 10 5000 ??? If your answer is 5000, then you are among the most who mistook. The actual answer is 4100. Count again and see if you get it right this time. 26