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# Mixture and Alligation Tricks – 2

Let us solve some CGL questions that may not seem to belong to Mixture-Alligation category, but are easier to solve via Alligation formula…

Q. 1)
Let the gain% of the remaining land be x%. Then
Given, 2/5 land is sold on loss and hence 3/5 land is sold on profit
So, Profit : Loss = 3:2
Hence 16 : (x – 10) = 3 : 2
16/(x – 10) = 3/2
or x = 62/3%
Q. 2)
His average speed for the entire journey = 61/9 km/hour
Time taken on foot : Time taken on bicycle = (9 – 61/9)/(61/9 – 4) = 4:5
Time taken on foot = 4/9 * 9 = 4 hours
Hence distance travelled on foot = (Speed on foot * Time taken on foot) = 4*4 = 16 km

Alternate method
This method is equally easy.
Let the distance travelled on foot be X km. Then distance travelled on bicycle = (61 – X)
Now he travelled for 9 hours. Hence
X/4 + (61 – X)/9 = 9
Solve for X
You will get X = 16 km

Q. 3)
Number of legs per head = 420/180 = 7/3
Now cows have 4 legs while hens have 2 legs
Cows : Hens = 1/3 : 5/3 = 1 : 5
Now total number of cows and hens = total number of heads = 180
Number of cows = 1/6 * 180 = 30
Q. 4)

A : B = 3 : 4 and B: C = 4 : 5
A : B : C = 3 : 4 : 5
Average score of classes A, B and C =

Q. 5)
The man spends 75% of his income, that means he saves 25%
Hence Expenditure : Saving = 75 : 25 = 3 : 1
Let the % increase in the savings be x.
I have written 3 : 1 as 30 : 10 so that (% increase in income – % increase in expenditure) could agree with 3 : 1 ratio. As we know 20 – 10 = 10, not 1.
So now from the figure we can see that  x – 20 = 30
Hence x = 50%

Q. 6)

If whole money is invested at 6%, then interest = 6% of 1500 = Rs. 90
If whole money is invested at 5%, then interest = 5% of 1500 = Rs. 75
Hence, Money invested at 6% :  Money invested at 5% = 10 : 5 = 2 : 1
Money invested at 5% = 1/3 * 1500 = Rs. 500