JAMB - Mathematics (1987 - No. 9)
By selling 20 oranges for N1.35 a trader makes a profit of 8%. What is his percentage gain or loss if he sells the same 20 oranges for N1.10?
8%
10%
12%
15%
Explicació
profit 8% of N1.35 = \(\frac{8}{100}\) x N1.35 = N0.08
Cost price = N1.35 - N0.10 = N1.25
If he sells the 20 oranges for N1.10 now
%loss = \(\frac{\text{actual loss}}{\text{Cost price}}\) x 100
\(\frac{1.25 - 1.10}{1.25}\) x 100
= \(\frac{0.15 \times 100}{1.25}\)
= \(\frac{15}{1.25}\)
= 12%
Cost price = N1.35 - N0.10 = N1.25
If he sells the 20 oranges for N1.10 now
%loss = \(\frac{\text{actual loss}}{\text{Cost price}}\) x 100
\(\frac{1.25 - 1.10}{1.25}\) x 100
= \(\frac{0.15 \times 100}{1.25}\)
= \(\frac{15}{1.25}\)
= 12%