Thursday, 2 November 2017

Maths - Short Cut Trick for Cube of 101 to 115 of Numbers

Cubes of 101 to 115 – 
This one will help you when the TIME is given for 3 years i.e., (A) = (1+r/100)3

(101)=1030301.
 (Remember in cubes of 101 to 115 the answer will be always in seven digits numbers.)

You can find this answer in three small steps –
1. Multiply 3 in only last digit of 101 i.e. in 1. It gives 103

2. Multiply 03 ( from 103) in last digit of 101 i.e. in 1 again, it gives 03. Write it after the first step answer like-10303 


3. Now you got 5 digits and only two digits are left. In this last step write the cube of last digit of 101 which gives 1 and add 0 before it i.e. 01 and write it after the second step answer i.e. 1030301. This is your answer.


(102) = 102 x 3 (in just last digit) =106.
             06 x 2 = 12 = 10612
             Cube of 2 = 8 i.e. 08 = 1061208 (answer)

(103)= 103 x 3 = 109
             09 x 3 = 27 = 10927
             (3)= 27 = 1092727 (answer)

(104)3  = 104 x 3 = 112
            12 x 4 = 48 = 11248
            (4)= 64 = 1124864 (answer)

(105) = 105 x 3 = 115
             15 x 5 = 75 = 11575
             (5)= 125 = 1157625 ( add 1 of 125 to just last digit of 11575)

(106)3  = 106 x 3 = 118
            18 x 6 = 108. Now add 1 of 108 to the last digit of 118, it gives 11908
            (6)3 = 216. Add 2 of 216 to the last digit of 11908, it gives 1191016(answer)

(109)3  = 109 x 3 = 127
            27 x 9 = 243. Add 2 of 243 to last digit of 127 = 12943
            (9)= 729. Add 7 of 729 to the last digit of 12943 = 1295029(answer)

(111)3  = 111 x 3 = 133
             33 x 11 = 363. Add 3 from 363 in last digit of 133 = 13663
            (11)= 1331.

As you already got 5 digits so you need only 2 digits but you have 4 digits in your hand i.e. 1331 so now add 13 from 1331 to the last two digits of 13663 and it gives 1367631(answer).


(115)3 = 115 x 3 = 145
             45 x 15 = 675. Add 6 from 675 to the last digit of 145 = 15175
             (15)= 3375. Add 33 from 3375 to the last two digit of 15175 = 1520875 (answer)

So the value of (115/100)3 = 1.520875.


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