in a sequence of five integers, the 3rd integer is the sum of the previous 2. the 4th integer is the sum of the previous 3 and the 5th integer is the sum of the previous 4. if the sum of the five integers is 248, what is the 3rd integer in the sequence.??
2007-11-19 13:36:04 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Steve A is correct, but I would solve it differently. You really only need two variables here.
let the 1st integer be a and the second be b. That means the 3rd integer is (a+b)
a + b + (a+b) + (2a+2b) +(4a+4b) =248
8a+8b=248
8(a+b)=248
a+b=31
since the 3rd integer is a+b, it's 31
2007-11-19 13:51:26 · answer #1 · answered by rob 6 · 0⤊ 0⤋
a + b + c + d + e = 248
a + b + c + d = e = 1/2 * 248 = 124
a + b + c = d = 1/2 * 124 = 62
a + b = c = 1/2 * 62 = 31
2007-11-19 21:46:07 · answer #2 · answered by Steve A 7 · 0⤊ 0⤋