I had 'one and a half hours' corrected to 'one and a half hour', which is ungrammatical in UK English, so am reporting my answer as an acceptable addition.
Well, at least we learn that डेढ़ is singular in Hindi.
(I've reported it as well.)
An hour and a half. But not "One and a half hour". It has to say "One and a half hours."
Is anyone still looking at the reports, I wonder? In three months they haven't fixed this. I wonder how many people have reported it in that 3 months?
Duolingo, once again written by people who clearly don't actually speak English
They might not speak (UK / NA) English, but they speak the language we want to learn.