На что надо умножить данное число, чтобы в произведении получить 1: а) 1/2 б) 5/7 в) 4 г) 11 д) 3 1/3 е) 5 2/5 ж) - 7 з) - 5/9

1) на 2:

1/2 * 2 = 2/2 = 1,

2) на 1 2/5:

5/7 * 1 2/5 = 5/7 * 7/5 = 35/35 = 1,

3) на 1/4:

4 * 1/4 = 4/4 = 1,

4) на 1/11:

11 * 1/11 = 11/11 = 1,

5) на 3/10:

3 1/3 * 3/10 = 10/3 * 3/10 = 30/30 = 1,

6) на 5/27:

5 2/5 * 5/27 = 27/5 * 5/27 = 135/135 = 1,

7) на - 1/7:

-7 * (-1/7) = 7/7 = 1,

8) на - 1 4/5:

-5/9 * (-1 4/5) = - 5/9 * (-9/5) = 45/45 = 1

1/2 * 2/1 = 2*1/1*2=2/2=1

5/7 * 7/5 = 35/35 = 1

4 * 1/4 = 4/1 * 1/4 = 4/4 = 1

11 * 1/11 = 11/11 = 1

3 1/3 * 10/3 = 10/3 * 3/10 = 30/30 = 1

5 2/5 * 5/27 = 27/5 * 5/27 = 1

-7 * (-1/7) = (-7/1) * (-1/7) = 7/7=1

-5/9 * (-9/5) = 45/45 = 1