They are about 50 km from here to there.
It is about 50 km from here to there.
A million euros are a lot of money.
A million euros is a lot of money.
We are leaving on the 21th of August.
We are leaving on the 21st of August / on August 21.
How did the exercise go? Well, I think I got the six wrong.
Well, I think I got the sixth (question) wrong.
There were two hundreds people at the concert.
There were two hundred people at the concert.
I got about the 50% of the answers correct.
I got about 50% of the answers correct.
He is tall one meter and eighty.
He is one meter eighty tall. He is 1.8 m tall.
They won the match three at zero.
They won the match three nil / three zero.
Three hundred dollars is about three hundred and twenty euros.
Hundreds of people went on the demonstration.
Three weeks is a long time when you are in prison.
60 square meters is enough for me - I don’t need much space.
It is seven meters long / high / wide.
Approximately 75% of Americans believe in alien abduction.
How is the test going? I am up to number seven.
Today is the twenty third of May. / Today is May the twenty third. / Today is May 23 / 23 May.
The final score was three one (3-1).
When hundred, thousand, billion are preceded by another number (e.g. three hundred) no -s plural is required. You can say hundreds, thousands etc to mean ‘several hundred / thousand’ (e.g. Hundreds / thousands of people are becoming victims every day).
Quantities are considered singular (e.g. three kilos is ..., 500 km is ...).
When referring to measurements note the word order: I am two meters tall (verb + measurement + adjective).
The definite article (the) is not required before percentages (the 10%) or questions in a test (I found the number three difficult).
Dates can be said in various ways. When writing, it is best to avoid -th, -st and -rd, because you may attach them to the wrong number (e.g. March 21th instead of March 21st or simply March 21).
Sports scores are said without a preposition: We won six four (6-4).