Sales rise from £400 a week to £504 a week. calculate the percentage increase

26%

Step-by-step explanation:

percent change = (new number - old number)/(old number) * 100%

Here, the new number is £504, and the old number is £400.

percent change = (£504 - £400)/(£400) * 100% =

= £104/£400 * 100% = 0.26 * 100% = 26%

it's equivalent, so we can say that its equal.

let's call the denominator x and the numerador is 18 less then denominator, x - 18.

multiply

2.x = 5.(x - 18)

2x = 5x - 90

90 = 5x - 2x

90 = 3x

x = 90/3

x = 30

so:

-4

step-by-step explanation: