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 $2.7 billion in candy.
Assuming 3,500 calories consumed results in a person gaining 1 lb (0.45 kg) in weight, estimate how many pounds (or kilograms) of weight the American population will gain. Add a comment below to post your entry.
The winner will receive public acknowledgement of their estimation skills, and I will send them a portion of the candy “tax” I collected from my kids.
Yes, we tax our kids for a portion of their candy collection, as mom and dad provide “infrastructure” and “chaperone” services.
It’s a useful lesson in taxation.
(We tax at a 33% tax rate.)
Mostly it is an excuse to reduce the amount of sugar they will otherwise end up consuming.
For my kids, it’s an excuse to get rid of the candy they don’t like anyways.
Good luck and Happy Halloween!
Entries will be accepted for next 72 hours, and only entries posted as comments below will be considered. A winner will be announced next week.
UPDATE as of Friday, November 4TH AT 12PM ET: New entries are welcome, but not eligible to win, as contest has closed.
329 thoughts on “A Sweet Estimation Question”
HI Victor
Based on data given and some assumptions, my estimates is that Americans will gain 36m kg of weight.
Assumption is that one candy will cost 1$, and will give approx 100 calories. Which means 2.7 billion candies bought generating 2.7 trillion calories. And it takes approx 7500 calories to gain one kg so 2.7 trillion calories will give 36m kg weight?
385,714,285 Lb
The total number of calories: 222 227 673 525
The total number of pounds gained:
63 493 621
Estimtate price a piece of candy: $ 0.3 (since your kid bought 160 pieces each and it would cost $ 48 for each kid as a reasonable budget);
Total actual spent on candy (tax excluded): $ 2.7B*0.66=$ 1.78B;
Total pieces of candy sold: $1.78B/$0.3=5.94B pieces candy;
Estimated total number of population buying candy: 0.3B(US population) *40%=0.12B;
Pieces/person: 5.94B/0.12B=49.5 pieces;
Each piece has calaries: ~ 1000;
Total calaries comsumed: 49500
Estimtated weight gained: 49500/3500 = 14 lb
Total weight gained for American population gained: 14* 0.12B=1.68B lb
347,142.86 kilograms
I worked with what I had handy. There were three bags of candy at my work that people brought from last night. I averaged calories per bag, and assumed the prices of the bags.
$12 Bag 1 = 530 cal in 7 pieces = at 95 pieces/bag = 7200 cal/bag
$11 Bag2 = 560 cal in 7 pieces = at 60 pieces/bag = 4800 cal/bag
$10Bag3= 680 cal in 15 pieces= at 100 pieces/bag= 4500 cal/bag
Avg Bag = $11 Avg cal/bag = 5500 cal
$2.7B /$11bag=250M bags sold at 5500 cal/bag = 1,375×10^9 cal
divided by 3500 cal/lb = ~400M lbs
and Im off to run on the treadmill now 🙂
Happy Halloween!
Hi Victor,
I will do it in a quite simple way. I am estimating that the majority of the candy sales come from snickers/mars/twix bars that I estimate to be sold in 10-unit packs of 100 calories/unit and at a price of $2 per pack. I am not from the US so I might be wrong on that.
This would lead me to a 1.35bn of packs sold, a 13.5bn candys sold and a total of 1350 bn calories (actually I’d say it’s kcal).
In terms of weight gain, Halloween would result on a 386m pounds gain that will add up to the weight gain during Thanksgiving and Christmas!!!
Have a great day!
Assume $1 of candy = 250 calories
250 calories/dollar x $2,700,000 = 675,000,000 calories
Given 3,500 calories = 1 lb of weight gain, then Americans will gain a total of 192,857,142.86 lbs (675,000,000/3,500).
Bonus: Assume American population is 300,000,000 then each American will gain approximately .643 lbs (192,857,142.86/300,000,000).
avg calories per candy 200 (assumption)
avg cost per candy 1.14 (assumption)
Total spend on candies 2,700,000,000.00
total no of candies 2,368,421,052.63
Total calories 11,842,105.26
3500 calories 1 ib
weight gained from 11842105 calries 3,383.46 lb
308,571,428 LB