Facebook Interview Question: Let's pretend you are sending... | Glassdoor

Interview Question

Online Marketing Specialist - SMB's Interview Menlo Park, CA

Let's pretend you are sending out emails to encourage SMB's

  to advertise with Facebook. Each email to each SMB costs $1. After you send the emails, .5% of the SMBs sign up. How much did you pay for each person that signed up? I had to keep asking clarification questions. "How many people did I send to?" Then he said, "Let's pretend there were 1,000." Then I got the answer from there... I believe it's just a way to assess how you think and not exactly to get the correct answer.

Interview Answer

10 Answers



hmmm on May 19, 2013

Isn't it $20?

really on Jul 31, 2013

The answer is $200. .5% means that 1 in every 200 people sign up 1/200=.5%

 If the answer was $20, this would mean the 5% of people sign up (1/20=5%).

Hopefully this helps!

Nick on Sep 2, 2013

Isn't the obvious answer $5? You sent the email to 1000 people, 0,5% sign up. 0,5%*1000 = $5 as one sendout costs $1.

Lisa on Oct 18, 2014

I believe it's a trick question, based on phrasing. "Each email to each SMB costs $1. ... How much did you pay for each person that signed up?" Unless I'm misreading this, you paid a buck per regardless of the eventual sign-up status.

Anonymous on Jun 12, 2015

There's no need to know how many emails were sent. 200 emails for every 1 signup, and $1 for every email, means $200 for every 1 signup.

Anonymous on Jul 23, 2015

$200 per signup is wrong.

Each email is $1. You sent 1000 emails. That equates to $1000 spent total, nothing less, nothing more.

0.5% of your emails were successful. 1000 emails * 0.05% = 50 successful emails.

At $200 each, 50 successful emails, or sign ups, would cost you $10,000, far more than the $1000.

Dividing the $1000 by the 50 signups = 1000/50 = $20 which means that you paid $20 for every person that signed up.

What threw most of you off was relying on the 1/200. It was not 1 signup for every 200 emails. That's a 0.005% success rate (1 in 200 = 5 in 1000 = .005). It was 0.05%. (1 in 20 = 10 in 200 = 50 in 1000 = 0.05%.

Let's sharpen our math skills, folks.

Good luck with your interviews. And don't vote for Trump.

Anonymous on Jan 23, 2016

The person above would have been right, but s/he used the wrong number. 5% is .05. 0.5% is .005. It is $200. Regardless, still don't vote for trump.

Anonymous on Jan 23, 2016

Let me clarify this question. The total sent is 1000 people, so you spent $1000 dollars regardless. The successful rate is 0.5% according to the one who post this question, which is 0.5%*1000=5. From 1000 sent, you got 5 signed up. You spent $1,000 on these emails, divided by 5 people who signed up from these email. You spent $200 on each signed up.

Danica on Mar 13, 2016

If you count the cost of those 99.5% deplorable emails as sunk cost, your cost of each sign-up is $1.
It's very normal to delete those unsuccessful emails form your server and forget about them.

I am with HER.

Vlad on Oct 22, 2016

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