Like xcr440 said, those are the size of your jets. Your pilot jet size is 75, and your main jet size is 180. Jets are essentially small tubes that the gas in your carb flows through. The number reffers to the size of the tube... the bigger the number, the bigger the tube and the more gas that flows through it. The different jets control gas flow through the carb at different throttle positions and so the effect of the particular jet on fuel delivery depends on throttle postition. The pilot jet has a large impact on fuel delivery at low throttle postions and a small impact on fuel at full throttle. The main jet is opposite and has a small impact at low throttle and large impact at full throttle.
The number of "turns" reffers to the air screw setting, not the jets. The air screw is on the outside of the carb and controls the ammount of air that flows in the fuel stream. More turns means more air and a leaner air/fuel mixture, less turns means richer. You set the air screw by screwing it inward untill it lightly stops, then screw it out the number of turns specified for your sled. A service manual or probably any repair shop/dealer can tell you what the jets and air screw setting should be for your sled... or if you post, i'm sure someone on here knows. Make sure not to confuse the air screw and the idle control screw though.
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