Respuesta :

x = 40 * 3 / 15
x = 120 /15
x = 8

answer
A. 8 
the answere is A, 8 because 3 x 5 = 15 and in order for these to to be qual the bottom and the top must be multiplied by the same number, meaning you divide 5 inot 40 in order to get 8, your answer.