Answer: 3.6hours
Explanation:
Since we are given the information that Eleniz is using her phone all day and that her battery life is down to 2/5 and it drains another 1/9 every hour.
The number of hours that the battery last will be:
= 2/5 ÷ 1/9
= 2/5 × 9/1
= 18/5
= 3.6 hours
Therefore, the battery will last for 3.6hours