Ballpark — May 25, 2026
Answers to that day's 5 daily estimation questions.
About how much caffeine is in a 12-oz cup of brewed coffee?
~140 mg
A typical 12-oz brewed coffee often lands around 100–200 mg of caffeine.
About how many grams of table salt are in one teaspoon?
6 g
A teaspoon of salt is heavier than sugar—often around 6 grams.
What is the voltage of a standard AA battery?
1.5 V
Most disposable AA batteries are rated at 1.5 volts.
About how many times does a person blink per minute on average?
~15 blinks/min
Many people blink roughly 10–20 times per minute.
About how tall is the average adult man in the US?
~175 cm
Average adult male height in the US is around 5'9".