Answer:
4
Step-by-step explanation:
Candle is lit every 10 minutes :
Number of candles lit in 55 minutes:
Starting from 0 minute ; Numbe rod candles lit on 55 minutes = 6
1st candle burns out after 40 minutes
Second burns out after 50 minutes
Third will burn out after 60 minutes
Hence Number of candles still burning :
Number of candles lit - Number of candle burnt out
6 - 2 = 4 candles
