The cost per unit of electricity during a 4 year period is…

The cost per unit of electricity during a 4 year period is as follows: Year 1, $0.5 per unit; Year 2, $1.0 per unit; Year 3, $1.5 per unit; Year 4, $2 per unit. If a factory spent equal dollars on electricity each year, what was the average cost of a unit of electricity during the 4 year period?

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #32403