document.write( "Question 1140751: Bonus: The number 15 is the smallest positive number which is a sum of two consecutive numbers, three consecutive numbers, and five consecutive numbers:
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document.write( "15 = 7+8
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document.write( "15 = 4+5+6
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document.write( "15 = 1+2+3+4+5
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document.write( "What is the largest number under 1000 that satisfies the same conditions? \n" );
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Algebra.Com's Answer #761253 by greenestamps(13200)![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "(1) The sum of 3 consecutive numbers is 3 times the number in the middle; the sum of 5 consecutive numbers is 5 times the number in the middle. So any number that can be written as the sum of both 3 consecutive numbers and 5 consecutive numbers must be a multiple of both 3 and 5, and therefore must be a multiple of 15. \n" ); document.write( "(2) The sum of 2 consecutive numbers is always odd. \n" ); document.write( "(3) From (1) and (2), the numbers that can be written as the sum of 2, 3, or 5 consecutive numbers are all the odd multiples of 15. \n" ); document.write( "(4) The largest odd multiple of 15 less than 1000 is 975. \n" ); document.write( "ANSWER: 975 \n" ); document.write( " |