If the ratio of red candles to blue candles Avianna bought was 5:3, then the total ratio was 5+3 = 8.

If 5 represented 45 candles in the total ratio, then 8, the actual ratio, represents 8*45 = 360 divided by 5 is 360/5 = 72 candles.

If the total number of candles was 72, then the number of blue candles is 72 candles - 45 candles = <<72-45=27>>27 candles

# Answer

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On her birthday, Avianna bought red candles and blue candles in the ratio of 5:3. If Avianna had 45 red candles on her birthday, how many blue candles did she have?
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27
On her birthday, Avianna bought red candles and blue candles in the ratio of 5:3. If Avianna had 45 red candles on her birthday, how many blue candles did she have?
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