which is less .25% or .06%

Question

which is stronger, .25% or .06% for medication?

Answer 1

Which is less:  0.25% or 0.06% ?

6 things is less than 25 things, so 0.06% is less than 0.25%.

.

Which is stronger, 0.25% or 0.06% for medication?

Can't tell.  You could be asking about concentration (0.25% would be stronger), dilution (0.06% would be stronger) or something else.  The problem is we don't know what 0.25% and 0.06% refer to.