Each of three investments has a 20% of becoming worthless within a…

Each of three investments has a 20% of becoming worthless within a year of purchase, independently of what happens to the other two investments. If Simone invests an equal sum Q in each of these three investments on January 1, the approximate chance that by the end of the year, she loses no more than 1/3 of her original investment is

Its source gives only the correct option, without the working.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #43752