Last night, I took my kids out for an American children’s holiday known as Halloween.
Kids (and some ahem… adults) dress up in costume (I was a penguin this year), go door-to-door, saying “Trick or Treat” and get free candy from the neighbors.
My three kids brought back a record 420 pieces of candy. 
In today’s New York Times, I learned that in the weeks leading up to this holiday, Americans purchased $2.7 BILLION dollars in candy.
So here’s my challenge for you.
Assuming all of that candy is consumed by someone in America, estimate the total number of calories represented by $2.7 billion in candy.
Assuming 3,500 calories consumed results in a person gaining 1 lb (0.45 kg) in weight, estimate how many pounds (or kilograms) of weight the American population will gain. Add a comment below to post your entry.
The winner will receive public acknowledgement of their estimation skills, and I will send them a portion of the candy “tax” I collected from my kids.
Yes, we tax our kids for a portion of their candy collection, as mom and dad provide “infrastructure” and “chaperone” services.
It’s a useful lesson in taxation.
(We tax at a 33% tax rate.)
Mostly it is an excuse to reduce the amount of sugar they will otherwise end up consuming.
For my kids, it’s an excuse to get rid of the candy they don’t like anyways.
Good luck and Happy Halloween!
Entries will be accepted for next 72 hours, and only entries posted as comments below will be considered. A winner will be announced next week.
UPDATE as of Friday, November 4TH AT 12PM ET: New entries are welcome, but not eligible to win, as contest has closed.
329 thoughts on “A Sweet Estimation Question”
If we want to estimate the total amount of weight that the US population gained as a result of the candy sold for Halloween, there’s a few steps that we should take. First, Since we’re given $2.7B as the total dollar amount spent on candy, we need to determine the number of pieces of candy that represents by dividing by the average price of a piece of candy. Then we need to multiply that number of pieces by the average calories of a single piece of candy to get the total calories consumed. Once we have the total calories, we can divide by the calories per pound, given to us here as 3,500 to get the total number of pounds gained by people in the US as a result of Halloween candy.
1. To start off, lets assume that we could buy a bag of candy with 50 pieces of candy for ~$10. That would mean each piece of candy cost, on average, $0.20. Then we can divide 2.7B by $0.20 to give us 13.5B pieces of candy sold.
2. Then if we assume that a single piece of candy is ~50 calories, we can multiply the 13.5B pieces by 50 to get a total of 675B calories coming from the candy.
3. We can then divide the 675B calories by 3,500 which gives us ~190M pounds gained by people in the US.
Initially, that may seem high, but if we consider the fact that there are ~320M people in the US that is just over half a pound per person which seems reasonable.
2.7 B in candy will add 57,857,142 pounds to the american population.
1. Halloween candies are usually hard candies. Assume 20 calories per candy, and assume 15 cents per candy. We have 2.7 billion in total of the spending, that leads to a total of 18 billion candies consumption (2.7 billion / 0.15). This leads to a total of 360 billion calories.
2. If 3500 calories results an increase of 1 lb, with a total of 360 billion calories, we have a gain of around 102.86 million lb (360 billion / 3500). So the American population will gain a total weight of 102.86 million with a 2.7 billion dollars of consumption in candies during Halloween week.
347142 kg
America gains
771,500 lbs
Let’s assume that a bag of candy is about ~$4. That makes roughly 600 million bags of candy.
Each bag of chocolate generally has 10 servings (eg. 8 hershey kisses in 80 piece bag, 3 kitkats in a 30 kitkat bag). Each serving of chocolate candy is generally ~200 calories. Every bag of hard candy, like lollipops, has maybe double the number of servings, but fewer calories for each serving, say 100 calories. So about the same number of total calories — 2000 — per bag.
That makes roughly 2000 calories per bag*600 million bags = 1.2 trillion calories. Divided by ~3500 calories is about ~350 million pounds, or about 1 lbs per person. Now, this doesn’t account that for kids, gaining a pound requires much fewer than 3500 calories — perhaps 2000. And that kids are probably the predominant consumers of the candy (aside from taxes their parents take). And that not all children celebrate Halloween. So I’d say it’s probably closer to 2 lbs just on the basis of a lower caloric requirement for weight gain. And more if you have a really good costume.
Hi Victor,
1.4 trillion calories leading to an estimated 170 million kilograms gained seems fair.
580.000.000 lbs
About 28,571 lbs
Total revenue =$ 2700 million
Assume price per unit of candy =$2
Assume calories per unit of candy = 250 cal
Therefore, $ 2700 million /$2= 1350 million bars of candy consumed.
1350 million * 250 = 337,500 million calories consumed.