`"a) Zaokrąglamy do setek":

$k=14\underline{0}7\approx 1400$  

$l=788\underline{9}6\approx 78900$  

$m=239\underline{0}7\approx 23900$  

$n=1079\underline{6}1\approx 108000$  

$o=3479\underline{9}9\approx 348000$  

 

$\text{b) Zaokrąglamy do tysięcy}:$  

$k=1\underline{4}07\approx 1000$  

$l=78\underline{8}96\approx 79000$  

$m=23\underline{9}07\approx 24000$  

$n=107\underline{9}61\approx 108000$  

$o=347\underline{9}99\approx 348000$