SOLUTION: A high-performance drone started its flight with a full battery charge. During the first phase (Takeoff and Ascent), it used 30% of its total capacity plus an additional 8 mAh. Aft

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Question 1210596: A high-performance drone started its flight with a full battery charge. During the first phase (Takeoff and Ascent), it used 30% of its total capacity plus an additional 8 mAh. After this phase, it entered the second phase (Data Collection), where it used 60% of the remaining charge plus an additional 12 mAh. At the end of the mission, the remaining battery charge was 136 mAh less than the charge consumed during the Data Collection phase. Find the battery capacity used during the Takeoff and Ascent phase.
Answer by greenestamps(13327) About Me  (Show Source):
You can put this solution on YOUR website!


Full charge to start:

x

Used in takeoff and ascent phase: 30% plus 8

.3x%2B8

Remaining:

x-%28.3x%2B8%29=.7x-8

Used during data collection phase: 60% of remaining plus 12

.6%28.7x-8%29%2B12=.42x%2B7.2

Remaining:

%28.7x-8%29-%28.42x%2B7.2%29=.28x-15.2

The amount remaining was 136 less than the amount used during the data collection phase:

.28x-15.2=%28.42x%2B7.2%29-136=.42x-128.8
113.6=.14x
x=113.6%2F.14=5680%2F7

Amount used during takeoff and ascent:

.3x%2B8=1760%2F7

ANSWER: 1760/7 mAh, or 251 3/7