contestada

Liz buys x markers at 90p each and 3 books at 1.20 each the total cost is 13.50
Solve to find x

Respuesta :

90p = 0.9
13.5 = 0.9x+3*1.2
0.9x = 13.5-3.6
0.9x = 9.9
x = 11