a boy perform 5 times a reaction and his reading are 2,2.1,2,2.2…

a boy perform 5 times a reaction and his reading are 2,2.1,2,2.2 but unfortunately 5th reading clearly not visible because a drop of chemical fall onto it.but luckily he have mean of all reading which is 2.please help him in finding 5th reading.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #19566