bonjour
2 - 5/3 x 4/7
= 2 - 20/21
= 42/21 - 20 /21
= 22 /21
2/3 + 5/3 : 6 /5
= 2 /3 + 5/3 x 5 /6
= 2/3 + 25 /18
= 12/18 + 25/18
= 37 /18
5/3 x ( 2/3 - 7/5 )
= 5/3 x ( 10/15 - 21/15 )
= 5/3 x - 11 /15
= - 55 / 45
= - 11 / 9
( 5/6 + 3/2 ) : ( 5/2 x 7 /4 )
= ( 5/6+ 9/6 ) : 35/8
= 14/6 x 8 /35
= 112/210
= 8 /15
( 2/7 - 2 ) : ( - 3 /5 + 33 /35 )
= ( 2/7 - 14 /7 ) : ( - 21 /35 + 33 /35 )
= - 12 /7 : 12 /35
= - 12/7 x 35/12
= - 35/7
= - 5
