Is 40% alcohol 2.5% stronger or 6.666’% stronger than 37.5% alcohol?

Question

So I’ve always considered myself fairly competent at maths and this has absolutely stumped me.

Initially my brain says obviously 40% alcohol is 2.5% stronger than 37.5% alcohol, but 2.5 is 6.666’% of 37.5, so is 40% alcohol actually 6.666’% stronger than 37.5% alcohol?

Someone help me I feel like I’m going mad

In: Mathematics

Answer 1

I think this depends on what how you are viewing it.

If you view it as an increase 37.5/100 to 40/100 then you would increase by 2.5%

If you are viewing it as a direct percentage comparison, 40/37.5 then you are increasing the 37.5% by 6.666%