(4X-K)/(1/2)-(5X-0.8)/(1/5)=(K-X)/(1/10)
2(4X-K)-5(5X-0.8)=10(K-X)
8x-2k-25x+4=10k-10x
-7x-12k+4=0
-7(-2)-12k+4=0
-12k+18=0
k=3/2
(4X-K)/(1/2)-(5X-0.8)/(1/5)=(K-X)/(1/10)
2(4X-K)-5(5X-0.8)=10(K-X)
8x-2k-25x+4=10k-10x
-7x-12k+4=0
-7(-2)-12k+4=0
-12k+18=0
k=3/2