sights are for close range and can be used in conjunction with a scope, usually the scope is raised so the sights can be seen under it. Also all rifle sights can be adjusted for windage (as in right to left to right and up and down), people often use the up and down windage adjustments to measure for the rate at which a bullet will fall and adjust accordingly, hence they can be used for distance, but they are technically wind age sights.
But, you probably wouldn't be adjusting the sights for bullet drop off on long distance shots if you have a scope so....yeah.