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Discover the magic number 1089 and its intriguing properties. Explore fun math riddles and geometric shape puzzles. Test your skills with entertaining math challenges. Unravel the tricks behind mathematical illusions. Engage in interactive math problem-solving activities. Enhance your math knowledge with exciting brain teasers. Explore the world of numbers and shapes in a playful way. Dive into the realm of Comenius Math and Science Studio for a fun learning experience.
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Think of three number digit The first digit must be two digits different from the third one
subtract the smaller number of the larger one • for example 782 – 287 = 495
now write the result in inverted form and add up two numbers • In this situation 495 + 594 = . . .
the result is number 1089
You probably think that the outcome depends on the initial numbers
Explanation • We first chose the three digit number • We wrote the number in reverse order of numbers • We subtracted the lower number from the larger • Decimal notation of the larger number: • Decimal notation of the lower number: • Subtraction:
a and c are integral numbers and so we always get multiples of 99 • The triple-digit multiples of the number 99 are 198, 297, 396, 495, 594, 693, 792, 891 • We see immediately that the sum of the first and third number is always 9 • So we get from the first numbers 900, 9 from the third numbers and 2*90 from middle numbers: 900 + 180 + 9 = 1089
Lamps • The teacher introduced a challenging task to his student: • I have three sons. • When you multiple their ages, the result is 36. • The sum of their ages is equal to the number of lamps in this street.
Lamps • The pupil thought about it and said : This is not enough for me, I can not say exactly how old they are. • The teacher answered. Well, the oldest son is called Charles • How old are the sons ?
Lamps - explanation • A multiple of three numbers must be 36 • 1*1*36=36 • 1*2*18=36 • 1*3*12=36 • 1*4*9=36 • 1*6*6=36 • 2*2*9=36 • 2*6*3=36 • 3*3*4=36
Lamps - explanation • the sum of three numbers must give the same results • 1+1+36=38 • 1+2+18=21 • 1+3+12=16 • 1+4+9=14 • 1+6+6=13 • 2+2+9=13 • 2+6+3=11 • 3+3+4=10
Lamps - explanation • you are getting two equal answers • 2+2+9=13 • the second result is correct, because the oldest brother is called Charles • number 13 is a number of the lamps in the street
Find which shapes can be drawn by a single line and give reasons why . The shapes which can be drawn by a single line, determine how to start, so that drawing could be done and give reasons. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
Solution 1. -two knots with an odd calculusof lines (right and left down), rest knotseven => can draw by a single line 2.-beginning in one of the odd nodes=> right or left down - all knots is even=> can drawby a single line and beginning any 3. - two knots with an odd calculus of lines(leftdown and on high), rest knotseven => can draw by a single line - beginning in one of the odd nodes => left on high or down 4. - all knots is even => can drawby a single line and beginning any 5. - all knots is even => can drawby a single line and beginning any
6. -two knots with an odd number of lines(down and up), the rest of knots even=> can draw • a single line • - begin with one of the odd nodes=> up and down • 7.-four odd knots (the maximum possiblenumber of odd knots is two, in one we start • drawing and we finish in the other)=> don´t by a single lin • 8.-all knots are even=> we can draw a single line and begin on any of them • 9.-all knots are even=> wecan draw a single line and begin on any of them
10.- four an odd knots(the maximum possible calculus odd knots is two, in one we will start • charting and in other we will finish)=> not draw by a single line • 11.- two knots with an odd calculus of lines (right and left on high), rest knots even => can • draw by a single line • - beginning in one of the odd nodes => right or left on high • 12.- two knots with an odd calculus of lines (down or on high), rest knots even => can • draw by a single line • - beginning in one of the odd nodes => down or on high • 13. -all knots is even=> can draw by a single line and beginning any
Funnymath Find x !