Version 1 Question 3 A mixture of 20 L of spirit and water contains 5% water ,how much water must be added to this to raise the percentage of water to 24%? 1. 5 Lt 2.4 Lt 3. 7 Lt 4. 8 Lt 5.10 Lt Method 1 20 Lt mixture contains 5% water. Water content is 1 Lt. Spirit is 19 Lt. Let y be the liters water be added to make it 24%. Total quantity is 20 + y Percentage of water => { (1+y)/(20+y) } x 100= 24 solve for y y= 5L Method 2 Create a table Sprit water 19L 1L Let x lit be added to the mixture. 19L 1+x Percentage of water must be 1+x=24%, so 19L sprit has to be 76%. if 19L=>76% (1+x)=>24% So (1+x) = 24 x (19/ 76 )= 6 x=5L 
