Mathemajics & Memory

The speed, capacity and efficiency of our memory depend, to a degree, on our mental make-up and the knowledge of divergent fields. Man's mind once stretched by new exercises as the ones below never goes back to its original dimensions.

SUM OF ALL DIGITS UPTO 10

1 to 10 i.e. 1+2+3+4+5+6+7+8+9+10

Multiply last number by a number next to it and divide by 2 : i.e. (10x11) /2 = 55

For 1 to 20, Add 100 to 55 , for 21 to 30, add 200 to 55, and like wise >>>>

11 to 20 >> 155

21 to 30 >> 255

31 to 40 >> 355 and carry on likewise.

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Multiplication of 2 nos whose diff is 2. >>> Say 14 x 16

1. Take Middle No. >>> 15

2. Squre it >>>> 225

3. Minus 1 >>>>> 224

4. Answer is 224.

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Multiplication of two 2 digit numbers whose 'ten' digits are same and 'unit' digits' sum is 10. Like 47 x 43 >>>>> 4 same 7+3 =10.

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1. Multiply Ten Digit Number by next whole no >>> 4 x 5 = 20

2. Multiply Unit Digit Nos together >>> 7 x 3 = 21

3. Answer is 2021

MEMORY TEMPERS PROSPERITY MITIGATES ADVERSITY, CONTROLS YOUTH AND DELIGHTS OLD AGE... LACTANTIUS