Question 47167
L=length
W=width
P=perimeter

P=2L+2W
BUT L=3W
So P=6W+2W
P=5W
P=48
So 48=5W
W=9.6
Recalling L=3w, 
L=3x9.6
L=28.8

So the length is 28.8 and the width is 9.6

I hope this helps,
Adam
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