I'm braindead this AM, math help needed.

Factual Questions
1

I did this same calculation a few days ago, but for the life of me, I have a block this morning, and I can’t remember the right sequence to get this calculation right. Someone with more coffee help me out please.:smack:

[ul]
[li]I need 20 sales appointments to be successful[/li][li]I successfully get an appointment in 30% of my prospecting calls[/li][li]How many prospecting attempts do I need to make?[/li][/ul]

Someone help me out with the formula for this please!

I just freaking did this last week, but now I’m just pissing myself off.

2

30% of all your calls = 20 successful calls.

0.30 * x = 20

x = 20/0.30 = 66.666… Therefore, you need to make 67 total calls.

3

20 sales is 30% of some number of sales.

Is this a homework question?

4

I’m assuming this isn’t homework so…

20/0.30 = 66.66…

5

No, I’m way too old for homework, believe me.

Just trying to help a fellow employee out with his time management. He’s a good salesperson, just can’t keep himself focused. I’m trying to coach him to take a more planned approach.

Math skills deserted me this morning. I was reversing the order of where the percentage went in the equation, got it now. Thanks!!

6

Actually, this problem looks more interesting that simple arithmetic.

The best real-world interpretation of “I successfully get an appointment in 30% of my prospecting calls” is that the probability of a call yielding an appointment is 0.3. Thus, it’s perfectly possible that 10 calls yield no appointments (this would be expected about 2.8% of the time).

Here’s a link to a Binomial Probability Calculator that solves this sort of problem. It yields the following results:

Number of calls to produce at least a 50% probability of at least 20 appointments: 66 (52.5%)

Probability of fewer than 20 appointments:
- with 70 calls: 35.4%
- with 80 calls: 13.5%
- with 90 calls: 3.9%
- with 100 calls: 0.9%

And there is no upper bound to the number of calls necessary to guarantee 20 appointments.

7

is coffee delivery as good as a numerical solution?