The salaries of A, B and C are in the ratio 1 : 3 : 4. If the salaries are increased by 5%, 10% and 15% respectively, then the increased salaries will be in the ratio

Let A's Salary = Rs. 100
Then, B's Salary = Rs. 300
And, C's Salary = Rs. 400
Salary has given in 1 : 3 : 4 ratio
Now,
5% increase in A's Salary,
A's new Salary = (100 + 5% of 100) = Rs. 105
B's Salary increases by 10%, Then,
B's new Salary = (300 + 10% of 300) = Rs. 330
C's Salary increases by 15%,
C's new Salary = (400 + 15% of 400) = Rs. 460
Then, ratio of increased Salary,
A : B : C = 105 : 330 : 460 = 21 : 66 : 92

Alternative
100 (A's salary) === 5%↑ ===> 105(A's increased salary)
300 (B's salary) === 10%↑ ===> 330 (B's increased salary)
400 (C's salary) === 15%↑ ===> 460 (C's increased salary)
Ratio of their increased salary = 105 : 330 : 460 = 21 : 66 : 92