Lesson: Testing the Answer Choices

Comment on Testing the Answer Choices

Great video!

Seems like that would eat up A LOT of time.
greenlight-admin's picture

There are instances when testing the answer choice can actually be faster than more conventional approaches.

Also, there may be times when you have no idea how to solve a math question using conventional techniques. In these instances, you can either skip/guess the question and move on, or you can start testing the answer choices.

In some cases, it may make more sense to skip/guess the question and use your time on other questions. In other case, it may make more sense to take the time to test the answer choices.

The "right" approach will depend on several factors, including your target scores and how much time you have remaining.

Nice way to arrange the information in a table and test the answers. Awesome!.

The most important thing is to understand the problem. If you don't understand how to interpret the word problem, you cannot correctly test the answer choices.
greenlight-admin's picture

Good point!

Can you solve it using algebra please?
greenlight-admin's picture

Which of the two questions (in the above video lesson) would you like me to answer?


2nd question
greenlight-admin's picture

Let C = # of cars at dealership
Let T = # of trucks at dealership
So, equation #1: C + T = 100

Now let's deal with the info about the used vehicles.
(1/2)C = # of used cars
(1/3)T = # of used trucks
So, equation #2: (1/2)C + (1/3)T = 42

Multiply both sides of equation #2 by 6 to get: 3C + 2T = 252
Multiply both sides of equation #1 by 3 to get: 3C + 3T = 300

Subtract bottom equation from top equation to get: -T = -48
So, T = 48

Answer: D


Hi dear
Can you help me to solve this using table
Cars and trucks over used and unused cards
greenlight-admin's picture

I'm not sure I understand your question.
I solve the question in the video using a table.


Hey Brent is this appreacoh right?

B = J + 8
Gives 2 cars to J + 8 - 2 he will have twice cars
so B = 2(J + 6)
J + 8 = 2J + 12
J = 4

But to Get B we should remember B - 2 = 2J
B = 2(4) + 2 = 10
greenlight-admin's picture

Question link: https://gre.myprepclub.com/forum/bobby-has-eight-more-cars-than-jackie-i...

You're close but....
Let J = the number of cars Jackie has INITIALLY
Let B = the number of cars Bobby has INITIALLY
So, if Bobby has eight more cars than Jackie, we can write: B = J + 8

Given: If Bobby gives two of his cars to Jackie, Bobby will have twice the cars that Jackie has.
If Bobby gives 2 cars to Jackie, then....
J + 2 = the number of cars Jackie has NOW.
And B - 2 = the number of cars Bobby has NOW.

So, if Bobby NOW has twice the cars that Jackie has, we can write....
B - 2 = 2(J + 2)

I'll let you solve the system of equations from here.

Does that help?

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