Dear student,

I think you have mistyped your words. In place of radio it should be ratio.

Now,

1m = 100cm

So, 3m 5cm = 300cm + 5cm = 305cm

And 2m 75cm = 200cm + 75cm = 275cm

Now, we have to find ratio of 305cm and 275 cm.

So, its very easy. Here see the steps :-

305 / 275 = 61 / 55. ( Divided both numerator and denominator by 5 )

So, the simplest ratio is 61 : 55