Coffee & Tea Brewing Math: Brew Ratios, Extraction, Water Recipes & Cost per Cup

What you'll build

What you will be able to do

Each lab ends with a concrete result that you build yourself and the checker confirms, cell by cell.

• Turn Theo's three daily recipes into brew water and beverage weights, account for the water the grounds keep, and work backwards from his mug to the dose and the brew water.
• Calculate the extraction yield of eight brews from their TDS readings, flag each one against a fictional target box, work out how much water tames a strong brew and pool the extraction of the whole log.
• Calculate the ratio and flow rate of Theo's shots, average the shot time per grind setting and highlight every shot outside his time window.
• Calculate how much concentrate Theo's cold-brew jar yields, how much of it goes into one drink, how many full drinks the batch makes and how much ice an iced pour-over needs.
• Dose a fictional hardness concentrate into distilled water, blend tap and distilled water to hit an alkalinity target, top up the hardness and look up a style preset – all in ppm as CaCO₃.
• Look up the leaf for today's teapot, the steep time of a later infusion and the total steeping time of a whole session, and mix boiling and cold water to the tea's temperature without a thermometer.
• Work out when each bag on Theo's shelf is ready to brew and how long it stays within its best-before window, how many days his stock lasts and how many bags to order.
• Price the beans in one latte, build the full home cost per cup including the machine's wear, work out how many months the machine needs to pay for itself and chart the cumulative costs of both options.