X= cost of one of tanya's items. tanya spent: 3x. tony spent: 4(x - 2.25)

equation: 3x = 4(x - 2.25)

solve: 3x = 4x - 9

3x - 4x = -9

-x = -9

x = 9

the individual cost of each person's item would be:

cost of one of tanya's = x = 9, cost of one of tony's = (x - 2.25) = 6.75

the cost of one of tanya's items was $9, and the cost of one of tony's items was $6.75,

the equation used was [ 3x = 4(x - 2.25) ].

check: tanya spent: 3x = 3(9) = 27

tony spent: 4(x - 2.25) = 4(9 - 2.25) = 4(6.75) = 27

tanya and tony both spent the same amount of money, tanya bought 3 and tony bought 4 items.