Răspuns:
A) (5 supra 6 +3 supra 4)×24 supra 19
(5/6+3/4)×24/19
=(10/12+9/12)×24/19
=19/12×24/19
=19/19×24/12
=1×2
=2
B) (1 supra 6 +7 supra 9 ×18 supra 17,
1/6+7/9×18/17
=1/6+7/17×18/9
=1/6+7/17×2
=1/6+14/17
=17/102+84/102
=101/102
D) (5 supra 12 -3 supra 18×4
(5/12-3/18)×4
=(15/36-6/36)×4
=9/36×4
=1/4×4
=4/4
=1
E) (11 supra 45-1 supra 30)×18 supra 19
(11/45-1/30)×18/19
=(22/90-3/90)×18/19
=19/90×18/19
=18/90
=9/45
=1/5