Question

the cost of 12 candles is equal to the selling price of 15candles find the loss per cent

Answer 1

C.P of 12 candles = x    (Say..)
S.P of 15 candles = x    (Given)
C.P of 12 candles = S.P of 15 candles = x
C.P of 1 candle = x/12
S.P of 1 candle = x/15
Loss = C.P-S.P
        = (x/12)-(x/15)  =  (5x-4x)/60  =  x/60
Loss% =  {(x/60)/(x/12)}*100%
           = (12/60)*100%
          =20%
LOSS = 20%

Answer 2

$\huge \mathbb{ \underline{ \underline\red{ \red{S{ \pink{O{ \blue{L{ \purple{U{ \orange{T { \red{I{ \blue {O{ \green {N{ \: :-}}}}}}}}}}}}}}}}}}}$

$\: \: \:$

$\tt{Let \: SP \: of \: 1 \: candle = Rs. \: 1} \:$

$\tt{SP \: of \: 15 \: candles = Rs. \: 15} \:$

$\sf \pink{ \underline{Hence, }}$

$\tt {CP \: of \: 12 \: candles = Rs. \: 15}$

$\tt{SP \: of \: 15 \: candles = Rs. \: 12} \:$

$\sf \pink{ \underline{Therefore \: Loss}}$

$\tt = CP - SP$

$\tt = 15 - 12$

$\large \boxed { \sf { \red{= Rs. 3}}}$

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