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## Comment on

Tips for the Input-Output Approach## Great tips

## Hi! If you were to solve this

## You're referring to the

You're referring to the question that appear at 6:23 in the above video.

You have: (1 + y/100 + x/100 + xy/100²) - 1

Rewrite first part with denominator 100²

We get: (100²/100² + 100y/100² + 100x/100² + xy/100²) - 1

Combine the first 4 terms: (100² + 100y + 100x + xy)/100² - 1

Factor top part to get: (100 + x)(100 + y)/100² - 1

Hmmm, I have a feeling your first expression, (1 + y/100 + x/100 + xy/100²) - 1, is incorrect.

Can you tell me how you got to (1 + y/100 + x/100 + xy/100²) - 1?

Cheers,

Brent

## At his regular hourly rate,

cost of a repair job as $336 and he was paid that

amount. However, the job took 4 hours longer than

he had estimated and, consequently, he earned

$2 per hour less than his regular hourly rate. What was

the time Don had estimated for the job, in hours?

(A) 28

(B) 24

(C) 16

(D) 14

(E) 12

sir how to solve this question?

## Hi Manjot,

Hi Manjot,

https://gmatclub.com/forum/at-his-regular-hourly-rate-don-had-estimated-...

Cheers,

Brent

## https://gmatclub.com/forum

sir please explain.

## At the risk of appearing

At the risk of appearing super lazy, I've seen Mitch (GMATGuruNY) post this great solution several times, and I think it's perfect: https://www.beatthegmat.com/og-13-ps-218-is-this-prob-really-doable-with... (Mitch's solution is the 4th post)

He also provides some great advice about the potential to skip (guess) and move on!

If you need any clarification regarding Mitch's solution, please let me know.

Cheers,

Brent

## Hi Brent,

Is there an easy way to solve the below question:

https://gmatclub.com/forum/from-2000-to-2003-the-number-of-employees-at-a-certain-company-increa-268694.html

## Here's my full solution:

Here's my full solution: https://gmatclub.com/forum/from-2000-to-2003-the-number-of-employees-at-...

Cheers,

Brent

## As you mentioned, an

If so, I assume you're just using it as an example to demo the *input-output* technique, even though there is an algebraic solution, correct?

Thanks.

## Yes, I'm using the input

Yes, I'm using the input-output for this question so I can demonstrate the strategy.

## Regarding the second question

Given the fact of question, "x percent greater than it's value on Wednesday", if we plug 0 into x which does not make sense at all ?

Please help !

Thanks.

## I believe you're referring to

I believe you're referring to the question that starts at 6:22 in the video above.

It's perfectly fine to have an "increase" of 0%. This Just means there was no increase.

For example, if Townville had a population of 10,000 in 2018, and a population of 10,000 in 2019, then we can say that the population "increased" 0% from 2018 to 2019. In other words, the population in 2019 is 0% greater than the population in 2018.

Does that help?