l=124/4=31 l1=31/2=15,5 L2=31*3=93 2p=2(93+15,5)=217cm
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Rombo:
lato $\small l=\dfrac{2p}{4} = \dfrac{124}{4} = 31\,dm.$
Parallelogramma:
lato maggiore $\small = 3×31 = 93\,dm;$
lato minore $\small = \dfrac{1}{2}×31 = 15,5\,dm;$
perimetro $\small 2p= 2(93+15,5) = 2×108,5 = 217\,dm.$
lato del rombo L = 124/4 = 31 cm
palallelogrammo :
base = 3L = 93 cm
lato obliquo = 15,5 cm
perimetro 2p = 31+186 = 217 cm