# Maths Trick Chapter 1

### Maths Trick Chapter 1

Similarly 36×76 , 6X6 =36 right hand side , (3×7)+6= 21+6=27 left hand side Required answer is 2736 NOTE If multiplication of last figures is less than 10 add zero before unit digit Ex 81×21 , 1×1=01,( 8×2)+1= 16+1=17 Required answer 1701 Method for multiplying numbers where the first number”s add up10 and and the second number’s digits are same 46X55 Here first number’s add up is 10 and second number “s digits are common i. e 5 Just multiplying last figures of both numbers 6×5 =30 put it at right hand side Again multiplying first figures of both numbers and add common digit of second number (4×5)+5 =20+5 =25 put it left hand side

Required answer is 2530 ( If multiplication is in unit in first step add zero before it) file:///D|/Documents%20and%20Settings/sanjay/Desktop/maths%20tricks/lesson1ur20. htm (1 of 3)6/25/2003 4:00:19 PM Lesson1 Multiplying numbers just over 100. 108 x 109 = 11772 The answer is in two parts: 117 and 72, 117 is just 108 + 9 (or 109 + 8), and 72 is just 8 x 9. Similarly 107 x 106 = 11342 HOW USEFUL IS THIS CALCULATION! EXAMPLE 1 Compute the amount and the compound intrest on Rs 10000. 00 on 2. years at4%per annum. Now 4×4=16 and 4+4=8 put 10 it becomes Rs 10816. 00 How simple ! o calculation no extra time ! Practice Test 1 Solve mentally these questions Note down your calculation time by watch (Suggested time 90 seconds) 22 X 28 35 X 35 48 X 42 73 X 33 12 X 92 48 X 28 28 X 22 37 X 88 91 X 66 118 X105 109 X108 112 X106 91 X 99 33 X 37 55X55 Now check your answer with the help of a calculator Back Home Next file:///D|/Documents%20and%20Settings/sanjay/Desktop/maths%20tricks/lesson1ur20. htm (2 of 3)6/25/2003 4:00:19 PM Lesson1 file:///D|/Documents%20and%20Settings/sanjay/Desktop/maths%20tricks/lesson1ur20. htm (3 of 3)6/25/2003 4:00:19 PM