Elephants, Tigers, and Leopards
A number and its reverse
Play Reverse and Add with a number and its reverse.
Your book, Maths Mela (Chapter 10), has a game called 'Reverse and Add'. Take a 2-digit number, like 27. Reverse its digits to get 72. Now add them: 27 + 72 = 99.
Try some more: 14 + 41 = 55, and 36 + 63 = 99. Notice something? The sum depends on the two digits added together. In 14 the digits add to 1 + 4 = 5, and the sum is 55. In 27 and 36 the digits add to 9, and the sum is 99.
Which numbers give 55? Their digits must add to 5: 14, 23, 32 and 41. Which give 88? Their digits must add to 8: 17, 26, 35, 44, 53, 62 and 71.
Can we get a 3-digit sum? Yes, when the digits add to 10 or more. 19 + 91 = 110, and 28 + 82 = 110 too. 110 is the smallest 3-digit sum we can get.
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