Question
Before a battle the ratio of tanks to planes in an army
was 5 : 3. During the war 1000 tanks were destroyed and 800 planes were destroyed. The ratio of tanks to planes became 2 : 1. What is the number of tanks after the war.Solution
let the number of tanks and planes be 5x and 3x after war tanks=5x-1000 and planes =3x-800 (5x-1000)/(3x-800)=2:1 5x-1000=6x-1600 x=600 Total tanks=3000-1000 = 2000
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