Răspuns:
5 / 9 x 3 / 4 = 5 / 12
7 / 15 x 5 / 14 = 1 / 6
5 / 6 x 3 / 20 = 1 / 8
Explicație pas cu pas:
5 / 9 x 3 / 4
9 = 3 x 3
5 / ( 3 x 3 ) x 3 / 4
= ( 5 x 3 ) / ( 3 x 3 x 4 )
= 5 / ( 3 x 4 )
= 5 / 12
7 / 15 x 5 / 14
14 = 2 x 7
15 = 3 x 5
7 / ( 3 x 5 ) x 5 / ( 2 x 7 )
= ( 7 x 5 ) / ( 3 x 5 x 2 x 7 )
= 1 / ( 3 x 2 )
= 1 / 6
5 / 6 x 3 / 20
6 = 2 x 3
20 = 5 x 2 x 2
5 / ( 2 x 3 ) x 3 / ( 5 x 2 x 2 )
= ( 5 x 3 ) / ( 2 x 3 x 5 x 2 x 2 )
= 1 / ( 2 x 2 x 2 )
= 1 / 8