5.8 Ongelmanratkaisu yhtälön avulla

Problem #1

2019-02-25T07:50:24+02:00

A charging station for a certain model of tablet devices is designed to prolong battery life by charging the first 60 percentage points (charge levels 0 .. 60 %) at full power and the last 40 percentage points (charge levels 60 … 100 %) at 80-percent power. The station charges one device from empty to full battery in 9 hours. It can be assumed that there is no battery consumption during the charging process. How many percentage points (changes akin to 1 % to 2% or 57 % to 58 %) does the charging station charge in one hour?

Problem #2

2019-02-25T07:51:19+02:00

During a phonecall of yours, one of your Bluetooth headphone starts to run out of battery. When you plug it in to its charger, it only has 10 percent of battery left. At the same time, the other headphone has still 25 percent remaining.

You carry on with your phonecall, and eventually the other headphone starts to run out of juice as well. You switch headphones, and the fresh one has 80 percent of its charge left.

Find the reduced proportion of charged percentage points to those spent during an active phonecall.

Tuntimuistiinpanot

2017-02-03T09:55:04+02:00