Question: Marge’s Chocolates

Comment on Marge’s Chocolates

thanks for these helpful videos :)
my question is how to do it depending on answers choices?
gmat-admin's picture

Good question!

Let's test answer choice B (17) first.
If Marge ate 17 chocolates on the last day, then she ate 14 chocolates the day before that, and 11 chocolates the day before that, and 8 chocolates the day before that, and 5 chocolates the day before that. We're told that she ate a TOTAL of 100 chocolates. Let's see if that's what we get. 17 + 14 + 11 + 8 + 5 = 55. No good. Since we need her to eat MORE chocolates, we'll test a BIGGER answer choice.

Let's test answer choice C (26).
If Marge ate 26 chocolates on the last day, then she ate 23 chocolates the day before that, and 20 chocolates the day before that, and 17 chocolates the day before that, and 14 chocolates the day before that. We're told that she ate a TOTAL of 100 chocolates. Let's see if that's what we get. 26 + 23 + 20 + 17 + 14 = 100 PERFECT!

Thanks

Even faster: consider test asnwering from C. Start with counting from 26, add 23, 20, etc.
gmat-admin's picture

Great idea! That would work too.

I used test answering starting with C, writing down:
26, 23, 20, 17, 14 = 100.

After, I thought of this as a faster way:
100;5 = 20 (3rd day) + 6 (she eats 6 more chocolates on day 5 then on day 3)= 26

Hope this is useful for anyone preferring non-algebraic solutions.

Regards, Glenn
gmat-admin's picture

Perfect reasoning, Glenn!!!

Thabo owns exactly 140 books, and each book is either paperback fiction, paperback nonfiction, or hardcover nonfiction. If he owns 20 more paperback nonfiction books than hardcover nonfiction books, and twice as many paperback fiction books as paperback nonfiction books, how many hardcover books nonfiction books does Thabo own?

A) 10
B) 20
C) 30
D) 40
E) 50

My approach:

Hardcover nonfiction=H
Paperbook nonfiction=20+H
Paperbook fiction=2(20+H)
SO,
2(20+H)+20+H+H=140
H=20.
Is that one variable approach is good to go?
gmat-admin's picture

That's a perfectly-executed approach. Nice work!

Thanks a ton sir.
But it hurts me as i hardly make algebric approach.
Such as, i completed 1st learning activities from word problem module (1-10).next learning activity is og questions.
I can comprehand all questions but can't able to find a starter but i solved thay problem through one variable approach.

Would you please give your thoughts?? What's my problem.
gmat-admin's picture

You're not alone. Many students struggle with translating words into algebraic expressions and equations.

You might want to review the following lessons:
- Assigning Variables: https://www.gmatprepnow.com/module/gmat-word-problems/video/902
- Writing Equations: https://www.gmatprepnow.com/module/gmat-word-problems/video/903

Be sure to answer lots of the linked questions in the Reinforcement Activities boxes for each of those video lessons. It will also help to review experts' solutions to help see how the process of creating equations works.

Keep at it. Your skills will improve with time and practice.

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