Sagot :
7/5 x 15/28+5/18 sur 10/9 = 105/140 + 5/18 x 9/10 = 21/28 + 45/180 = 21/28 + 1/4 = 21/28 = 7/28 égal à 1
= 7/5 * 15/28 + 5/18 : 10/9
= 105/140 + 5/18 * 9/10
= 105/140 + 45/180
= 3/4 + 1/4
= 1
= 105/140 + 5/18 * 9/10
= 105/140 + 45/180
= 3/4 + 1/4
= 1