Please help me with these

Question

1. -5/c = 1/3

2. k/8 = -2/5

3. 6/z = -3/5

Thank you

Answer 1

1. -5/c = 1/3.
Cross-multiply:
c = -15.

2. k/8 = -2/5.
Cross-multiply:
5k = -16,
k = -16/5 = -3 1/5.

3. 6/z = -3/5.
Cross-multiply:
-3z = 30,
Z = -10.