Required Mathematical Intelligence

Chapter 84

The lights in Shen Yaofang's house suddenly went out, which turned out to be a power outage.She lit the two candles prepared in advance and continued to review her homework until the call came again.Now known:

(1) The length of the two candles is the same, but the thickness is different;
(2) Thick candles can be lit for 5 hours, and thin candles can only be lit for 4 hours;

(3) When the call comes again, one candle head is 4 times the other candle head.

Excuse me, how long is the power outage (that is, the burning time of the candle)?

[Answer: Both candles were lit for 3 hours and 45 minutes, which is the blackout time. ]
(End of this chapter)