How to Calculate Faster than a Calculator - Mental Math #1 — Transcript

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1. 0:00before we start this video in 5 seconds
2. 0:03can you quickly tell me how much is 86 *
3. 0:0784 it is
4. 0:097224 I know many of you would have
5. 0:12struggled to find it in 5 seconds but I
6. 0:15am making a series of mental math videos
7. 0:18and after completing this series and
8. 0:20with a bit of practice you will be able
9. 0:23to do calculations like these faster
10. 0:25than a calculator that is at a lightning
11. 0:28fast speed yes yes even faster than the
12. 0:31snap of Thanos and you will be able to
13. 0:34amaze your friends and appear smarter in
14. 0:36front of
15. 0:38them okay so are you ready we will first
16. 0:42start with the very basic which is
17. 0:44multiplying any two digit number with 11
18. 0:48how would you multiply 43 with
19. 0:5111 yeah I know we can use the method we
20. 0:54had learned in school but it will be a
21. 0:57bit longer but using this trick it will
22. 0:59be super fast so write four and three
23. 1:03and in the center write 4 + 3 or 7
24. 1:07that's it answer is
25. 1:10473 although it's basic but it's super
26. 1:14fast now 54 * 11 write five and four and
27. 1:19in between write 5 + 4 or 9 amazing but
28. 1:24you might wonder what if the sum is
29. 1:27greater than or equal to 10 like 68 * 11
30. 1:32write 6 then 8 and in the middle it will
31. 1:34be 6 + 8 or 14 so take one to the carry
32. 1:39and add with six to make it seven so the
33. 1:42answer is
34. 1:43748 C lightning fast now you might be
35. 1:47thinking that I am sharing tricks only
36. 1:49for specific numbers but that's not
37. 1:52Mental Math don't worry this is only the
38. 1:54beginning as this is the first part
39. 1:57there are many more such tricks to come
40. 2:00now the trick I taught you also works
41. 2:02with three-digit numbers for example 35
42. 2:052 * 11 write three and two now in Center
43. 2:10first add both of them to get eight and
44. 2:13now add 5 + 2 or 7 here that's it we get
45. 2:203872 and if the sum is greater than N9
46. 2:23then just carry like the previous one
47. 2:26for example 5 74 * 11 so write five and
48. 2:30four here then in the middle write 5 + 7
49. 2:34or 12 and here 7 + 4 or 11 now carry one
50. 2:40here to make it six and then carry one
51. 2:42here to make it three so the answer is
52. 2:466314 awesome we are still faster than
53. 2:50the calculator now let us move to the
54. 2:53next trick which is multiplying two
55. 2:55two-digit numbers with the same first
56. 2:57digit and ending in five
57. 3:00like multiply 75 * 75 in 5 seconds you
58. 3:05might be blank right now am I correct so
59. 3:08the trick here is to multiply seven with
60. 3:10the next number or eight to get 56 and
61. 3:13then simply add 25 to it this will be 5
62. 3:176
63. 3:1825 okay now try 35 *
64. 3:2235 3 * 4 is 12 and then add
65. 3:2725 that's it faster than a calculator
66. 3:31isn't it now tell me in the comments
67. 3:33what will be 95 * 95 great now are you
68. 3:39ready for the next trick it is
69. 3:41multiplying two two-digit numbers with
70. 3:44the same first digit of both the numbers
71. 3:46and the sum of the ending digits is 10
72. 3:49for example 44 * 46 here the first digit
73. 3:54of both the numbers are the same which
74. 3:56is four and the sum of the ending digits
75. 3:59is four 4 + 6 or 10 now do four * its
76. 4:03next number or five which is 20 and then
77. 4:074 * 6 or 24 so the answer is
78. 4:122024 isn't this cool now let us try 67 *
79. 4:1763 6 * 7 is 42 and 7 * 3 is 21 so we get
80. 4:244 22 1 awesome we're still beating
81. 4:28calculators in spe speed okay now tell
82. 4:31me in the comments what will be the
83. 4:34value of 89 * 81 you are already doing
84. 4:38calculations faster like a human
85. 4:41calculator lastly don't forget to
86. 4:43practice this trick and you'll get even
87. 4:46faster if I get 10,000 likes in this
88. 4:49video I will make part two of it which
89. 4:52will be much more interesting and super
90. 4:54fun so good
91. 5:01[Music]