Quantitative - Alligation or Mixture

Quantitative - Alligation or Mixture
Question:-
Option (A)
1 : 9
Option (B)
1 : 10
Option (C)
5 : 9
Option (D)
4 : 9
Correct Option:
A
Question Solution:
Say he buys 1 litre of milk. He adds y litres water in it & sells it for x Rupees.
Total profit will be 33.3% that means profit is 5/3 & selling price is 5+5/3 = Rs 6.67

He sells at Rs 6 per litres & as he gets Rs. 6.67 that means he sold 6.67/6 = 1.11
So water added to 1 liter is 0.11
Hence Water to milk ratio is 0.11 : 1 or 1 : 9
Question:-
Option (A)
75%
Option (B)
72.5%
Option (C)
70%
Option (D)
67.5%
Correct Option:
B
Question Solution:
When one alloy having 7% gold is mixed with another alloy having no gold, the result is a new alloy with 5% gold. Hence, ratio of mixing is 2:5.
Question:-
Option (A)
1:3
Option (B)
2:3
Option (C)
1:2
Option (D)
None of these
Correct Option:
C
Question Solution:
Say you add x litres from Cask A & y litres from Cask B.
That means wine in final mixture will be 6x from Cask A & 9y from Cask B, i.e total wine will be 6x+9y
Same way total water will be 7x+4y.
Required solution need wine : water as 8 : 5
i.e. (6x+9y)/(7x+4y)=8/5
or 30x+45y=56x+32y
or 13y=26x
or x/y = 1/2
Hence x : y means 1 : 2
Question:-
Option (A)
170 kg
Option (B)
175 kg
Option (C)
160 kg
Option (D)
165 kg
Correct Option:
A
Question Solution:
Since the percentage of gold in both alloys is the same, any mixture of the two will contain the same percentage concentration of gold.
Hence, we get
First alloy: Gold: silver: Platinum
30 : 30 : 40
Second alloy: Gold: silver: Platinum
30 : 26 : 44