Question 923734
Two candles of the same height are lit at the same time. One burns down in 5 hours while the other burns down in 3 hours.
:
lets assume both candles start out at 15" high
then
the 1st candle burns 3" per hr
and
the 2nd candle burns 5" per hr
:
" After how many hours will the first candle be three times the height of the second?
let t = time in hrs for this to be true
12 - 3t = 3(12-5t)
12 - 3t = 36 - 15t
-3t + 15t = 36 - 12
12t = 24
t = 24/12
t = 2 hrs
;
:
see if this is true
12 - 3(2) = 6"
12 - 5(2) = 2"