Cost price = total sales - profit
To begin, we will first have to convert the gross profit to margin. Hence we have;
33 13= 1003× 1100\;\frac{1}{3} = \;\frac{100}{3} \times \;\frac{1}{100}31=3100×1001
Cross multiply
14\;\frac{1}{4}41 x 36,240 = 9060
Cost price = 36,240 - 9060 = 27,180