Question:
A mixture contains alcohol and water in the ratio 4:3. If 5 litres of water is added to the mixture the ratio becomes 4:5. Find the quantity of alcohol in the given mixture :
A12 ltrs
B20 ltrs
C22 ltrs
D10 ltrs
Answer:
D. 10 ltrs
Explanation:
alcohol : water = 4 : 3 = 4x : 3x If 5 litres of water is added to the mixture the ratio becomes 4:5 ⇒ 4x/(3x + 5) = 4/5 5 × 4x = 4(3x + 5) 20x = 12x + 20 8x = 20 x = 20/8 = 5/2 quantity of alcohol = 4x = 4 × 5/2 = 10 L