Average age of total 80 students from three classes, V, VI and…

Average age of total 80 students from three classes, V, VI and VII, is 13 years. Average age of 30 students of class V is 11 1/2 years. If average age of another 30 students of class VI is 12 1/2 years, what is the average aage of rest of 20 students of class VIII ?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #67382