counter for questions
Attaches to numbers to count questions, e.g., in exams, quizzes, or surveys. Often used in educational or testing contexts.
The exam has 50 questions in total.
The third question was the hardest.
このアンケートは10問です。
This survey consists of 10 questions.
I got 8 out of 10 questions right.
質問 is the general noun meaning 'a question' that you ask, while 問 is a counter attached to numbers to count questions (e.g., test items).
問題 refers to the actual question or problem item itself (e.g., on an exam), while 問 is only the counter suffix used to tally how many such items there are.
From the kanji 問 (question), used as a suffix/counter. The reading もん is a common on'yomi.
not questioning; letting pass; overlooking
consultation; inquiry; seeking an opinion
difficult question; difficult problem; perplexity
posing a question; setting a question; asking in a survey or test · question; question item
trial; hearing; interrogation
inspection; check; examination · checkpoint; security screening; police inspection
summons; calling to account
answering one's own question; wondering to oneself; soliloquizing
ask oneself; self-questioning
medical interview; history taking
blame; censure; reprimand
visit to console; sympathy call; comforting visit
inquiry; hearing; investigation
cross-examination; close questioning; demanding an explanation
foolish question; stupid question · my question; one's question
condolence visit; visiting the bereaved to offer condolences
interview; examination; questioning
one question
inquiry; consultation; asking a subordinate or expert
creation of exam questions
inquiring; asking