Grades 9-10 Video Solutions 2023-2023_9-10

Video Transcription

Video Summary

Mike's train journey took 16 hours. Starting with his phone half charged, he used the phone equally for calls, the internet, and idle time, each for \( x/3 \) hours. Calls deplete \( 1/32 \), internet \( 1/20 \), and idle \( 1/80 \) of the battery per hour. The combined battery depletion during the journey was calculated as \((1/32 + 1/20 + 1/80) \times x/3\) of the phone's battery. Given that he began with a half-charge, solving the equation for depletion equaling 0.5 determined the journey lasted 16 hours.

Keywords

train journey

battery depletion

phone usage

equation solving

16 hours