Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and equations ensures a solution.
If a certain culture of bacteria increases by a constant factor of x every y minutes, how long will it take for the culture to increase to ten-thousand times its original size?
1. x=10^y
2.In two minutes, the culture will increase to one hundred times its original size.
Since there are 2 variables (x,y) in the original condition, we need 2 equations to match the number of variables and equations. We have 1 each in 1) and 2), therefore C is likely the answer.
Using both 1) & 2) together,
In case of 1), x=10^6. Since the value is multiplied by 10^6 every 6 minute, the answer is 6 minute.
In case of 2), since the value is multiplied by 100 every 2 minute, it's 10,000times for 4 minutes and 1,000,000 for 6 minutes. Since 1) = 2), The answer is D.
If you know our own innovative logics to find the answer, you don't need to actually solve the problem.
www.mathrevolution.com
- The one-and-only World's First Variable Approach for DS and IVY Approach for PS that allow anyone to easily solve GMAT math questions.
- The easy-to-use solutions. Math skills are totally irrelevant. Forget conventional ways of solving math questions.
- The most effective time management for GMAT math to date allowing you to solve 37 questions with 10 minutes to spare
- Hitting a score of 45 is very easy and points and 49-51 is also doable.
- Unlimited Access to over 120 free video lessons at
https://www.mathrevolution.com/gmat/lesson
- Our advertising video at
https://www.youtube.com/watch?v=R_Fki3_2vO8
