Answer: 2.815 kilograms
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Work Shown:
1 layer = 0.5 kg
5 layers = 5*(0.5 kg) = 2.5 kg
icing = 15 g = 15/1000 = 0.015 kg
1 candle = 100 g = 100/1000 = 0.1 kg
3 candles = 3*(0.1 kg) = 0.3 kg
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The five layers combine to 2.5 kg. On top of that we have 0.015 kg of icing, and then finally the three candles add 0.3 kg more weight.
The total weight is therefore: 2.5+0.015+0.3 = 2.815 kilograms