Answer: k = 200/3
Step-by-step explanation:
If a variable, a varies directly with a variable, c, it means that as a increases, c increases and as a decreases, c decreases.
Also, If a variable, a varies inversely with a variable, b, it means that as a increases, b decreases and as a decreases, c increases.
The variable c varies directly with a and inversely with b. We would introduce a constant of variation, k. Therefore
a = kc/b
If c = 3/20 when a = 2 and b =5, then
2 = (k × 3/20)/5 = 3k/100
Cross multiplying, it becomes
3k = 100 × 2 = 200
k = 200/3
