a, 100/x +2 = 144/xb, 1/x + 1/x+2 = 12/35c, 60/x + 60/x+2 + 1/20 = 120/xd, 45/x+6 - 18/x = 1e, 60/x - 60/x+10= 1/5f, 50/x - 50/x+5 = 3/5g, 480/x - 10 = 480/x+44
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