Answer :
let x Ltr of 80% solution is mixed with 400-x ltr of 30% solution
ATQ we have x*80/100 + (400-x)*30/100 = 400*62/100
⇒ 80x + 12000 - 30x = 24800
⇒ 50x = 12800
x = 256 ltr
ANS- 256 ltr of 80% acid solution is required
ATQ we have x*80/100 + (400-x)*30/100 = 400*62/100
⇒ 80x + 12000 - 30x = 24800
⇒ 50x = 12800
x = 256 ltr
ANS- 256 ltr of 80% acid solution is required