GeekDad Puzzle of the Week: How to Calculate the Optimal Amount to Spend on Any Gift

Reading Time: 2 minutes


Have you noticed that those sleigh bells ringing and jing ting tingling too sound suspiciously like a cash register? Is this some sort of Pavlovian conspiracy between Toys R Us and the Salvation Army? I hear that noise and I become a Romero zombie lurching into the aisles to spend…spend…spend.

But not this year.

This year, I am adopting the persona of the rational consumer. My budget is my budget and I will not spend a dime more (mostly because I don’t have a dime more…). So I’m falling back on a strategy I outed a year ago on the now defunct Science Channel show Brink.

Here’s how to spread you budget EXACTLY across the people on your shopping list.

• First write down your TOTAL holiday gift-buying budget.
• Now list all the people you have to buy gifts for.
• Rank the importance of each of these people: write a number 1-10 with 10 being important in front of each person’s name.
• Now add all these ranks: if you have people ranked 10, 6, 5, 3, 3, 3, 2, 2, 2, 2, 1, your total would be 39.
• Set up an equation with this total (times a variable) equal to your budget—for me: 39x=$500
• Solve: x=$12.82
• Multiply x back into your priorities list: on someone ranked “10” you spend 10x or $128.20. On someone ranked 6 you spend 6x or $76.92.
• Evil laugh, for you have solved the age-old mystery of gift buying.

Above, you can see this method in action above with an unsuspecting shopper — actually a ringer, my friend Christiana. And by the way, if you’re in Southern California this holiday season (though my family and I moved to Colorado) please stop by the shop seen in the video, Serendipity Toys in Ojai, CA, where the owner, Joe, earned a Masters in Engineering at Berkeley in the 60′s. His train track set-ups are simply sublime and his store is that crowded, eclectic jumble you remember from your childhood.

As for this week’s puzzle, show your work as you use this equation (actually more of an algorithm…) to split your gift budget. Then submit the work and your answers to GeekDad Puzzle Central for your chance at this week’s $50.00 ThinkGeek Gift Certificate.

Get the Official GeekDad Books!