Original time
Floating Point : 2y
Fixed point : y
Floating point and fixed point instruction are in 2:3 ratio.
For simplicity assume there are 2 floating point and 3 fixed point instruction
Not original time 4y + 3y =7y -------------------1
Now speed of floating point increases by 20%. we need to convert this 'SPEED' into 'TIME' because we need to calculate ratio of original time and new time.
speed increased by 20% means , it becomes 120/100 of original.
And not time becomes Inverse of this i.e. 100/120 (Newtons formulae applicable to even Computer science.)
Now time for one floating point instruction becomes = 100*2y / 120 -A
simillarly time for one fixed point becomes 100*y/110 -B
we have 2 Floating and 3 fixed point instruction . hence total time 2A+3B = 800*y/132 ---------------2
Divide 1 by 2 gives answer A