$a)3,45762\approx 3,5$

$41,929123\approx 41,9$

$0,98615\approx 1$

$b)117,17265\approx 117,17$

$812,51427\approx 812,51$

$1267,27815\approx 1267,28$

$c)7182,71625\approx 7182,716$

$73,15256\approx 73,153$

$1,512671\approx 1,513$