There are two ways of using the infinitive as an adjective, 1. attributive, 2. predicative. Naturally 2. is a subject complement.
I'd like to do without commas, but 6 feels odd if it doesn't have commas.
Oi you, that's too much of a rip off by anyone's count! 6:4 is more than enough. Of course I'm the '6'.
Uncle asked: "What is three plus four?"
About three fourths of the earth's surface consists of water.
Three-fourths of the earth's surface is covered with water.
Two-thirds of the earth's surface is covered with water.
Three-fourths of the earth's surface is water.
One fifth of the earth's surface is covered by permafrost.
One third of the earth's surface is desert.
Our records show that the invoice No.1111 is still outstanding.
It is true that he is over seventy.
The whole population of New Zealand is 3,410,000, and one seventh of it are the Maori people.
The first was the school uniform.
One third of the population of that country cannot read.
Four-fifths of all the members were against the plan.
This dictionary contains about 40,000 headwords.
Two thirds of the employees of this company are engineers.
Three quarters of the members of this club are girls.