21c2/b8•b2 /14c

I think you’re using binomial coefficients, but the grouping isn’t clear from “21c2/b8•b2 /14c”. Could you confirm the exact expression? For example, do you mean one of these?

• (21C2) / (8C2) × (2) / (14C2)

If you meant that, here’s the calculation:

• 21C2 = 210
• 8C2 = 28
• 14C2 = 91

So the value is (210/28) × (2/91) = 7.5 × (2/91) = (15/2) × (2/91) = 15/91 ≈ 0.1648.

If you intended a different grouping (for example, 14C with a different missing parameter, or a different last binomial term), please rewrite with explicit parentheses, e.g.:

• [(21C2) / (8C2)] × [2 / (14Ck)] where k is 0,1,2, etc.
• (21C2) / [(8C2) × (2)] / (14Ck)

Tell me the exact expression (and which is n and k in each C(n,k)), and I’ll compute it step by step.