How to read words like テスト with ordinal numbers?

Question

Consider this:

テスト１, テスト２, テスト３ etc. (Taken from my exercise books. The tests are labelled as such up to 30)

(Question) Should numbers that are used with loanwords like テスト be read with いち,　に,　さん etc.? Or read as ワン, ツー, スリー etc.?

I feel that it's more consistent to use "English derivatives" all the way, than to have "English derivative"+"Japanese reading".

Answer 1

I am not sure why you feel it more consistent to use "English derivatives" all the way. Does it mean that, if you have an English-derived word in a sentence, the whole sentence should be made using only English-derived word? I think it is much better to read it in Japanese reading.

When reading mathematical variables or chemical formulae, often, non-specialists tend to read the subscripted number in English-derived reading if they are small enough. For example:

t1 (ティーワン)
H2O (エイチツーオー)　　

But when the number is large enough, or if the reading becomes complex enough, they switch to Japanese reading:

t60 (ティーろくじゅう)
C12H22O11 (シーじゅうにエイチにじゅうにオーじゅういち)　　

This is stupid. Probably non-specialists do not have enough knowledge to read large numbers in the English-derived way, but nevertheless do so for small numbers, and do not think about inconsistency. On the other hand, people with enough consideration do not pronounce it in an inconsistent way but read the numbers in the Japanese way regardless of the size of the number.

Answer 2

I think the most natural and usual way is using Japanese numbers (いち,　に,　さん...). テスト is a loan word, but it's a Japanese word. Think of it this way: should you use German numeral readings when using German loan words?

The English readings may be used for literary purposes, like chapter titles in a manga or book, for example, but they would be the exception.

Answer 3

There is no real anwser to your question: there is no way you should count. People around me use both in similar situations. All you need is to be consistent.