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”
let’s say:
total pounds=total calories / 3500 calories * 1lb
total calories=Ouantity of candies * calories per unit
Quantity of candies= total sales(2.7b)/price
now we need figure out the price and calories per unit.
let’s start with the price first.
we assume that there are 3 kinds of candies:
high-price: 20% ; $15 per bag
mid-price:60%, $5 per bag
low-price: 20%; $1 per bag
so the average price will be $6.2 per bag.
next, we need calculate the calories per bag.
we assume that we have two segments here:
high-calory:80%, 1000 calories
low-calory: 20%, 500 calories
so the average calories are 900 calories.
put all the numbers we have into the formula, we can gain that the total pounds Americans will gain are roughly 114 lb.
Hello,
Given:
$2.7 billion in candy sales
3500 calories = 1 pound of mass gain
Assumptions:
Every American gains weight equally and only via eating candies
Assuming all candies are of same size, quantity and sugar content and cost the same price
1 candy gives 150 calories
Cost of 1 candy =$1.5
Solution:
Since 1 candy =$1.5, $2.7 billion worth of candies = 18000000000 pieces of candy
Now, 1 candy gives 150 calories of energy
Hence, 18 billion pieces of candy = 18×10^9 X 150 = 270×10^10 calories of energy
3500 calories = 1lb of weight gain
Hence, 270×10^10 calories = 7.8×10^8 pounds of weight gain.
So the American population overall will gain 7.8×10^8 pounds which is 780 million pounds of weight gain.
Kashyap sridhar
If we assume that Halloween candy costs $6 per pound and divide that by the $2.7 B sold, then Americans ate 450,000,000 pounds of candy. If each pound of candy contains about 2,000 calories, then Americans consumed a total of 900 Billion calories. If 3,500 calories leads to a pound of weight gained, then as a whole Americans gained a total of 250,000,000 pounds collectively. With about 325,000,000 citizens, the average amount of weight gained was 3/4 of a pound.
1) Number of calories in 2.7Md$ of candy = Number of calories in 1 candy * Number of candy bought by 2.7 Md$
Assuming 1$ buys 1 candy, Number of candy bought by 2.7 Md$ = 2.7 Md
Number of calories in 1 candy: assuming an average person needs 2 000 calories per day.
Being able to get the equivalent of 3 meals in 10 candies seems too few, at least for an european like me. It means that a candy is less than 2000/10 = 200 calories.
However, having to eat 100 candies to get to the 2 000 calories seems too much. It means that a candy is more than 2000/100 = 20 calories.
My averaging, we’ll consider that one needs to eat 50 candies to get to the 2 000 calories. It means that a candy is worth 2000/50 = 40 calories.
Thus, Number of calories in 2.7Md$ of candy = 40 * 2.7 Md
= 4.10 * 2.7*10^9
env = 4 * 3 * 10^10
env = 120 Md calories.
The total number of calories represented by $2.7 billion in candy is 120 billion calories.
2) Let’s note N the Number of calories in 2.7Md$ of candy. Let’s note G = Gain_weight_of_the_American_population.
G = N/3500 because consuming 3500 calories means gaining 1 lb of weight. (formula is consistent in units: [calories/(calories/lb)] = [lb])
G = 120*10^9/(35*10^2)
G env = 120 /40 *10^7
G env = 3*10^7
G env = 30 M lb.
The American population will gain 30 million pounds.
Rq: American population = 300 million p.
Average gain per person = 30 million lb/300 million p = 0.1 pound. Seems coherent.
Assuming Population = 300 million
$2.7B/300M = $2700M/300M = $9 per person
Assuming one USD buys 50 candies
$9 buy 450 candies
Assuming each candy contains 50 calories
450*50 calories per person = 22,500 calories per person
22,500/3,500 pounds = 6.43 pounds per person
Avg calories per candy = 100
2.7b/100 = 27m calories for all halloween candies
27m/3500 =7714 lb (7714/0,45= 17142 kg) of weight the american population will gain
estimate the total number of calories (C) = 3.5 trillion calories
weight the American population will gain = C/3500 = 445 mln kg
90 Million
First, I estimate how many calories per ounce your candy has. I used Twizzlers and Reese’s and assume they’re representative of the U.S. Twizzlers have 3.375 cal/gram and Reese’s have 5.15. Avg of 4.3.
With 454 grams/lb, there is 1950 cal/lb. of candy consumed.
At $2.7B at retail, Amazon sells candy at roughly $3/lb. Add 20% for average US retail sales (or $3.60/lb). That’s 750MM lbs consumed, or 1.46 trillion calories.
If it takes 3000 calories to translate to a pound of weight, you get 417 million pounds of candy consumed in the U.S.
Reese’s peanut butter cups is the most popular candy in the US and contains around 500 calories. Assuming that the average halloween price per unit is $1 (which is low-balling it since it will predominantly be bought in bulk) we can use this as a proxy for the average $1 candy calorie intake: $1 = 500 calories –> $7 = 3500 = 1 lbs.
Thus, $2.7 billion/7 = 385.7 million lbs,
With the american population at 330 million –> 385.7/330 = 1.17 lbs on average per american citizen.