1.15k+2.5k-2.3k
k=3.5
15k+2.5k-2.3k=15.2k k=3.5 ⇒ 15.2*3.5=53.2
15k+2.5k-2.3k=(15+2.5-2.3)*k=15.2k=15.2*3.5=53.2