Sagot :

Bonjour,

68 * x/68 = 52

68/1 * x/68 = 52

68x/68 = 52

x = 52 * 1 = 52

74 * x/74 = 38

74/1 * x/74 = 38

74x/74 = 38

x = 38 * 1 = 38

57/90 * x = 57

x = 57 * 90/57

x = 5130/57 = 90