Fewer Vs. Less MGMAT SC guide

dv2020 wrote:In the MGMAT SC guide page 194

We have less than twenty dollars.---> is correct

Whereas on page 199 The sentence is corrected by replacing fewer for less

The composer is regarded more for the quality of her works: in two decades, she has written FEWER than twenty complete works, including just three symphonies.

The thumbrule is use fewer for countable nouns. The thumbrule is not violated but I am missing some concepts here. Can someone especially someone from MGMAT clear me on this.

Thanks...

dv2020 wrote:
We have less than twenty dollars.---> is correct

When we have things such as 20 Dollars, 20 Litres. That is basically the unit, then they actually refer to the Underlying thing(whose unit we are mentioning)
Eg: I have two litres of milk.Here Its basically talkin about milk which is non-countable
Similarly when we say twenty dollar, we talk about MONEY which is non-countable and hence we use LESS

The composer is regarded more for the quality of her works: in two decades, she has written FEWER than twenty complete works, including just three symphonies.

Here we are talking about 20 complete works, which is countable. So use fewer.

Thanks...