Maths magazine by Jaison

Maths Magazine

Prepared by J. Andrew Jefferson (Team Lead) Guru Prasad Madeesh Sooryaraj Kevin Narayan Class VI B SBOA School and Junior College

Table of Contents 1. Finger Multiplication of 6,7,8,9,10 Tables — Page 3 2. Crossword ——————————-——— Page 6 3. Life of Pi π ————————————— Page 7 4. Fun with Numbers —————————— Page 9 5. Jokes ———————————————- Page 11

Finger Multiplication of 6,7,8,9,10 Tables Here is a Math Trick to easily multiply the numbers from 6 to 10. This method can be useful and easy for kids to understand and calculate the 6 to 10 multiplication tables just by using their hands. Follow the steps given in the example below. Step 1: Place your fingers as in the below image and consider the value of fingers in each hand to be 6, 7, 8, 9 and 10 in the order from small finger to thumb.

Step 2: Choose the numbers that you want to multiply. Say you want to multiply 7x8. Step 3: Put together the fingers whose values you want to multiply. Ring finger in your left hand for 7 and middle finger in your right hand for 8 as shown below.

Step 4: Now count the touching fingers and the ones below them. The number you get will be the tens. Example: 5. Since this number is the tens place we have to consider as 5x10 = 50.

Step 5: Now multiply the fingers above the ones touching of the left hand and the ones in the right hand. The number you get will be the units. Example: 3x2 = 6. Step 6: Add the Tens place number you got in Step 4 and Ones place number you got in Step 5. Example 50 + 6 = 56.

7 X 8 = 56 This method can be used for any table from 6 to 10.

Crossword 1 2 3 4

Across 3. Natural numbers along with zero are called ______ Numbers 4. LCM is ______ Common Multiple 6. A line drawn from the centre of a circle to a point on the circle 9. These lines do not intersect 10. Region enclosed by a cord and an arc 11. Natural numbers start from this number Down 1. A line connecting 2 points on the circle 2. Region between a pair of radii 5. Angle greater than 90 degrees 7. The longest cord in a circle 8. A closed figure made up of line segments See answer in last page... 7

Life of Pi - π This is the story about Pi π 22/7 used for calculating the area of the circle. The ancient Babylonians calculated the area of a circle by taking 3 times the square of its radius, which gave a value of pi = 3. One Babylonian tablet indicates a value of 3.125 for pi , which is a closer approximation. Rhind Papyrus (ca.1650 BC) gives us insight into the mathematics of ancient Egypt. The Egyptians calculated the area of a circle by a formula that gave the approximate value of 3.1605 for pi. The first calculation of pi was done by Archimedes of Syracuse(287–212BC) one of the greatest mathematicians of the ancient world. Archimedes approximated the area of a circle by using the Pythagorean Theorem to find the areas of two regular polygons: the polygon inscribed within the circle and the polygon within which the circle was circumscribed. Since the actual area of the circle lies between the areas of the inscribed and circumscribed polygons, the areas of the polygons gave upper and lower bounds for the area of the circle. 8

Archimedes knew that he had not found the value of pi but only an approximation within those limits. In this way, Archimedes showed that pi is between 3 1/7 and 3 10/71. A similar approach was used by Zu Chongzhi (429–501), a brilliant Chinese mathematician and astronomer. Zu Chongzhi would not have been familiar with Archimedes’ method but because his book has been lost, little is known of his work. He calculated the value of the ratio of the circumference of a circle to its diameter to be 355/113. To compute this accuracy for pi, he must have started with an inscribed regular 24,576-gon and performed lengthy calculations involving hundreds of square roots carried out to 9 decimal places. Mathematicians began using the Greek letter π in the 1700s. Introduced by William Jones in 1706, use of the symbol was popularized by Leonhard Euler, who adopted it in 1737. Do you know : Pi has been known for almost 4000 years, but even if we calculated the number of seconds in those 4000 years and calculated pi to that number of places, we would still only be approximating its actual value . 9

Fun with Numbers 111111111 x 111111111 = 12345678987654321 12 + 3 - 4 + 5 + 67 + 8 + 9 = 100 1x8+1=9 12 x 8 + 2 = 98 123 x 8 + 3 = 987 1234 x 8 + 4 = 9876 12345 x 8 + 5 = 98765 123456 x 8 + 6 = 987654 1234567 x 8 + 7 = 9876543 12345678 x 8 + 8 = 98765432 123456789 x 8 + 9 = 987654321 The number 142857 is special. When you multiply it the digits found in the answer stay the same, just in a different order. Check it out: 1 x 142857 = 142857 2 x 142857 = 285714 3 x 142857 = 428571 4 x 142857 = 571428 5 x 142857 = 714285 6 x 142857 = 857142 What happens when you multiply it by 7 ? 7 x 142857 = 999999 And it doesn't stop there: 142 + 857 = 999 14 + 28 + 57 = 99 142857 x 142857 = 20408122449 20408 + 122449 = 142857 Thatâ&#x20AC;&#x2122;s one amazing number! 10

Fun with Numbers 1 = One 10 = Ten 100 = One hundred 1000 = One thousand 1000000 = One million 1000000000 = One billion 1000000000000 = One trillion 1000000000000000 = One quadrillion 1000000000000000000 = One quintillion 1000000000000000000000 = One sextillion 1000000000000000000000000 = One septillion 1000000000000000000000000000 = One octillion 1000000000000000000000000000000 = One nonillion 1000000000000000000000000000000000 = One decillion Followed by Undecillion Duodecillion Tredecillion Quattuordecillion Quindecillion Sexdecillion Septendecillion Octodecillion Novemdecillion Vigintillion Googol (the number 1 followed by 100 zeros) Centillion (the number 1 followed by 303 zeros) Googolplex = The number 1 followed by a googol zeros (there literally isn't enough room in the universe to write this number). 11

Jokes!!! 1. What is a mathematician's favourite dessert? Pi! 2. How can you make seven even? Take away the "s"! 3. Why was the math book sad? Because it had too many problems! 4. Why was six afraid of seven? Because Seven ate(8) Nine! 5. If you had 8 apples in one hand and 5 apples in the other, what would you have? Really big hands! 6. Teacher: Why are you doing your multiplication on the floor? Student: You told me not to use tables. 7. Parallel lines are strangers Because they do not meet.

Crossword Answer