Ailigation Method :
The existing solution has 40% sugar. And sugar is to be mixed; so the other solution
has 100% sugar. So by alligation method:
The two mixtures should be added in the ratio 5 : 1.
Therefore, required sugar =
X 1 = 60 gm.
Quicker Method : Here you can use direct formula :
quantity of sugar added =
300 (50 - 40)
= 60 gm.
100 - 50
A mixture of 40 litres of milk and water contains 10%
water. How much water must be added to make 20%
water in the new mixture?
A petrol pump owner mixed leaded and unleaded petrol
in such a way that the mixture contains 10% unleaded
petrol. What quantity of leaded petrol should be added
to 1 litre mixture so that the percentage of unleaded petrol
15 litres of a mixture contains 20% alcohol and the rest
water. If 3 litres of water be mixed in it, the percentage of
alcohol in the new mixture will be: