Entre 10 de fevereiro e 10 de novembro, o preço da mercadoria subiu 275% se o preço do kilo em 10 de novembro e 67,50 Qual era o preço em 10 de fevereiro?

At february 10th the price was $18

Step-by-step explanation:

If there was an increase of 275%, then the final price is the original price (100%) added by the amount increased, therefore it is 375% of the original value. In order to calculate how much that is we can apply a rule of three in a way that $67.5 is realated to 375% in the same proportion as 100% is related to "x", where this variable is the price in february 10th.

$67.5 - > 375%

$x - > 100%

67.5/x = 375/100

375*x = 67.5*100

375*x = 6750

x = 6750/375 = 18

At february 10th the price was $18