do the math

(you) do the math

Figure out or put together the information for yourself. Do the math—can't you see that he's just using you to get ahead in the company? What happened? They convinced you to give them a lump sum as an "investment," and now they've cleared out of town. You do the math.
See also: math

do the math

1. Literally, to do a bit of arithmetic calculation. Primarily heard in US, South Africa. Well, let's just do the math to see if you have enough in your savings account to afford a new car.
2. To figure out or put together information for oneself. Primarily heard in US, South Africa. Do the math—can't you see that he's just using you to get ahead in the company?
See also: math

do the math!

work it out for yourself (used to suggest that the conclusion to be drawn about something is obvious). North American informal
Math is the American abbreviation of mathematics . When the phrase is used in British English, it is usually as do the maths .
2004 BBC News: Business I was faced with the choice of either topping up by using paid holiday or a vast reduction in earnings and a financial struggle when I least need it. You do the maths!
References in periodicals archive ?
When you do the math, you quickly see how looking away from the road even for a split second is courting disaster.
Let's do the math. The table gives an average contribution of petroleum products to total costs of production of 2.64 percent, ranging from 0.11 percent (in banana production), to 20 percent (in transport).
To avoid this, do the math to see if there's a financially dominated plan that's always a worse deal.
(Well, the brain does do the math. It just doesn't show its work.)--Tom Siegfried, Editor in Chief
Now let's do the math together: 2.5 X 20,000 pounds X 40% = 20,000 pounds of sequestered stable carbon per acre.
Do the math. Look at percentages rather than dollars and cents.