ANSWER
The percentage decrease is 10.4%.
EXPLANATION
To calculate percentage decrease, use the formula,
Percentage decrease
[tex] = \frac{new \: price - old \: price}{old \: price} \times 100\%[/tex]
Yesterday the price of coffee was 2.40. This is the old price.
Today the price is 2.15. This is the new price.
[tex] = \frac{2.15 - 2.40}{2.40} \times 100\%[/tex]
[tex] = \frac{ - 0.25}{2.40} \times 100\%[/tex]
[tex]= - 0. 10416667 \times 100\%[/tex]
[tex] = - 10.416667\%[/tex]
To the nearest tenth, we have:
[tex] - 10.4\%[/tex]
Therefore the percentage decrease is 10.4%.
