The sum of first five terms of an AP are 50 and sum of next 5 terms of an AP are 125 write AP
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Step-by-step explanation:
S₅ = 50, S₅₋₁₀ = 125 to find A.P
sum of first 10 terms S₁₀ = 175
S₅ = 50 = n/2[2a + (n - 1)d]
=> 50 = 5/2[2a + 4d]
=> (50*2)/5 = 2a + 4d
=>2a + 4d = 20............................1
S₁₀ = 175 = 10/2 [2a + 9d]
=> (175*2)/10 = 2a + 9d
=> 2a + 9d = 35.....................2
equation 2 - 1
=> 5d = 15 => d = 3
2a + 4*3 = 20 => 2a = 20 - 12 => a = 4
therefore A.P is 4, 7, 10, 13, 16............
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