Aptitude - Ratio and Proportion - Discussion

Hey guys, I am going to ask one question. The question is here;

In a city, 40% of the adults are illiterate while 85% of the children are literate. If the ratio of the adults to that of the children is 2:3, then what percent of the population is literate?

Thank you @Krishna you explained in the simple way.

m-2:1-w.
m-1:2-w.
2:1 4-1=3 difference by addition of water,
2:4
3 * 60/3 = 60.

Thanks @Vinita Singh.

This Question can also be solved as:

2x/x = 60,
X = 30.
New ratio is 1:2.
Where 1 part is milk.
Nd 2x is water put the value of x.
Hence water = 60.

It is said in the question that the ratio is 2:1 which means 40 litres of milk and 20litres of water should be there. Now the new ratio should be 1:2 of the obtained result (40 litres stands for 1parts and 20 litres stands for 2 parts) now in this mixture there is 40 litres of milk and 80 litres of water. But there is already 20 litres of water is there in the previous 40 litre of milk so we deduct that 20 litres therefore we get new amount of water i.e. is 60 litres.

2x + x = 60.

Volume of water X = 20
Volume of milk y = 2x = 40.

Now keeping the volume of milk fixed i.e y = 40
Therefore y+2y=z,
40+(2*40)=z,
Z=120.

Therefore volume of water is 120-40=80.
But volume already present is 20 so additional water to be added is 80-20=60 litre.

In the tank we have 60 litter:

Case 1
For ratio 2:1
We have 40:20

Case 2
For ratio 1:2:

Now the thing is that as you can see from case 2 ratio which is 1:2 it means we have to twice the value of water and we not want to change milk quantity which is 1 so,

(2/3*60) + 20(from precious case 1 water ratio)
= 60.

We have used 2/3 from basic ratio formula.

Ratio= 2+1=3.
Mix= 60litr,
60/3=20,
Ratio= 2:1 then multiply by 20,
2*20=40 and 1*20=20,
Next ratio 1:2.

1 2
40 20 Cross multipy then the value is 80and 20.
80-20 = 60 is the answer.

Take 3 empty glass.

We have to count 60 ltr with the ratio,
Now fill 2 glass with milk 20ltr = 40ltr.
And,

Now fill 1 glass with water 20ltr,
Mix milk 2(glass) + water 1(glass) = 3glass.
The mixture is now of 20(milk)+20(milk)+20(water) = 60ltr.

Now we want a new ratio 1:2.
For that how much water to be added in existing 60ltr solution.

We have 40ltr of milk in 60ltr and 20ltr water.
If we added 60ltr of water now then milk is 40ltr and water is (20+60) 80 which is 1:2.