achandak wrote:
Eg. There are three times as many adults as children.
There are two times as many birds as zebras
How do debug these questions in the form of an equation?
Sent from my Redmi 4 using
GMAT Club Forum mobile appI love that you've asked this question. This is one of the most common simple math errors to make, and the fact that you've recognized the error means you're already ahead of most people who make it.
The trick to 'debugging' these is to test out some simple numbers to make sure your equation makes sense.
For example, if there are two times as many birds as zebras, it would make sense to have 20 birds, and 10 zebras, just based on the language. 20 is two times as many as 10.
So if you wrote down the equation '2b = z', try plugging in those numbers to make sure that your equation makes sense.
2b = z
2(20) = 10
Hmmm... that's not correct. So, your equation must be wrong.
But if you wrote down 'b = 2z', try plugging in the numbers now:
b = 2z
20 = 2(10)
20 = 20
That's a correct statement, so the equation 'b = 2z' was the right one.
If you develop a habit of doing this, you can do it very quickly in your head every time you write an equation like this one. I tend to make this mistake myself, so I always just quickly plug in some simple numbers in my head that fit the problem, to double check that I translated correctly.