Răspuns:
Explicație pas cu pas:
1.
(2 - 1/2)(3 - 1/3)(4 - 1/4) *1/5 = (4/2 - 1/2)(9/3 - 1/3)(16/4 - 1/4)*1/5
= 3/2 * 8/3 * 15/4 *1/5 = 3
2.
(1 - 1/2)*(1 + 0,5) = (1 -0,5)*(1 + 0,5) = 0,5 *1,5 = 5/10 *15/10 = 75/100 = 3/4
3.
(2 - 1/2): 1/2 = (4/2 - 1/2) *2 = 3/2 * 2 = 3
4.
(4 - 1/4) *8/15 = (16/4 - 1/4) * 8/15 = 15/4 *8/15 = 8/4 = 2
5.
(1/2 + 1/5)*20/7 = (5/10 + 2/10) *20/7 = 7/10 *20/7 = 2
6.
(1 - 3/4) : 1/4 = (4/4 - 3/4) : 1/4 = 1/4 : 1/4 = 1
7.
(2 + 1/3) : 7/6 = (6/3 + 1/3) : 7/6 = 7/3 : 7/6 = 7/3 *6/7 = 6/3 = 2
8.
(2 + 1/2)*4/5 = (4/2 + 1/2)*4/5 = 5/2*4/5 = 4/2 = 2
9.
(2 - 1/2) : 3/10 = (4/2 - 1/2) : 3/10 = 3/2 * 10/3 = 10/2 = 5
10.
30(1/3 - 0,3) = 30(1/3 - 3/10) = 30(10/30 - 9/30) = 30* 1/30 = 1
11.
(1/2 - 1/5)*10/3 = (5/10 - 2/10)*10/3 = 3/10 *10/3 = 1
12.
1/2 : 0,5 - 1 = 1/2 : 5/10 - 1 = 1/2 : 1/2 - 1 = 1 - 1 = 0
Sper ca ai inteles, incearca singur celelalte exercitii.