Bonjour, pouvez vous m’aider. Merci bcppp

Bonjour,
1) 1/5 * 2/3 = 2/15
2) 1/5 + 2/15 = 3/15 + 2/15 = 5/15
15/15 - 5/15 = 10/15 = 2/3
ou
x + 1/5 + 2/15 = 1
x + 5/15 = 1
x = 15/15 - 5/15 = 10/15 = 2/3