Find the three numbers in A.P., whose sum is 15 and the sum of whose s

1.	Find the three numbers in A.P., whose sum is 15 and the sum of whose squares is 77.
Answer» Let the three numbers in AP be a-d, a, a+dThen,\xa0sum = a-d+a+a+d=153a = 15So, a = 5Also, Sum of squares = 83(a-d)2+a2+(a+d)2=83(5-d)2+25+(5+d)2=8325+d2-10d+25+25+d2+10d=8375+2d2=832d2=8d=+2 or -2When d = 2,The numbers are 3, 5, 7When d = -2,The numbers are 7, 5, 3

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