Verified answer

x+y+z/3 = 21.21

x=0.8z

y=0.3z

0.8z+0.3z+z=63.63

2.1z=63.63 

z=30.3

 x=0.8*30.3 =24.24

 y=0.3*30.3  =9.09

12.3   and  6

15.7   and 7

S1=12.3*6 =73.8

S2=15.7*7  =  109.9

S1/S2=0.67

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