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[Akashdeep13]

Stuck in one problem.Please help me understand it

Raymond borrowed $450 at 0% interest.If he pays back .5% of the total amount every 7 days,beginning exactly 7 days after the loan was disbursed, and has thus far paid back $18, with the most recent payment made today,how many days ago did he borrow the money?

(A) 6
(B) 8
(C) 25
(D) 42
(E) 56

[[email protected]]

Hi Akashdeep13,

We're told that Raymond pays 1/2% of $450 every 7 days and that he's paid a total of $18 so far.

1% of $450 = $4.50
4% of $450 = $18

That 4% has been paid in 1/2% increments (one increment every 7 days), so there have been 8 payments so far.

(8)(7 days) = 56 days

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

[Brent@GMATPrepNow]

Stuck in one problem.Please help me understand it

Raymond borrowed $450 at 0% interest.If he pays back .5% of the total amount every 7 days,beginning exactly 7 days after the loan was disbursed, and has thus far paid back $18, with the most recent payment made today,how many days ago did he borrow the money?

(A) 6
(B) 8
(C) 25
(D) 42
(E) 56

Another approach:
1% of $450 = $4.50
So, 0.5% of $450 = $2.25
So, Raymond pays $2.25 back each week.

Raymond has paid a total of $18 so far.
$18/$2.25 = 8
So, there have been 8 payments so far.

(8)(7 days) = 56 days

Answer: E

[Akashdeep13]

Hi Akashdeep13,

We're told that Raymond pays 1/2% of $450 every 7 days and that he's paid a total of $18 so far.

1% of $450 = $4.50
4% of $450 = $18

That 4% has been paid in 1/2% increments (one increment every 7 days), so there have been 8 payments so far.

(8)(7 days) = 56 days

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

I have one doubt.. he started to pay after 7 days.. so shouldn't the days 56+7?

[DavidG@VeritasPrep]

Hi Akashdeep13,

We're told that Raymond pays 1/2% of $450 every 7 days and that he's paid a total of $18 so far.

1% of $450 = $4.50
4% of $450 = $18

That 4% has been paid in 1/2% increments (one increment every 7 days), so there have been 8 payments so far.

(8)(7 days) = 56 days

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

I have one doubt.. he started to pay after 7 days.. so shouldn't the days 56+7?

Think of it this way:

Payment 1 happens on day 7.
Payment 2 happens on day 14 (or 2*7)
Payment 8 happens on day 56 (or 8*7)

[Akashdeep13]

Hi Akashdeep13,

We're told that Raymond pays 1/2% of $450 every 7 days and that he's paid a total of $18 so far.

1% of $450 = $4.50
4% of $450 = $18

That 4% has been paid in 1/2% increments (one increment every 7 days), so there have been 8 payments so far.

(8)(7 days) = 56 days

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

I have one doubt.. he started to pay after 7 days.. so shouldn't the days 56+7?

Think of it this way:

Payment 1 happens on day 7.
Payment 2 happens on day 14 (or 2*7)
Payment 8 happens on day 56 (or 8*7)

I understood what you said, but my doubt was that he started to pay after 7 days of amount disbursed. After 7 days, he started to pay every 7 days. So shouldn't the first payment after 14 days?

[DavidG@VeritasPrep]

Hi Akashdeep13,

We're told that Raymond pays 1/2% of $450 every 7 days and that he's paid a total of $18 so far.

1% of $450 = $4.50
4% of $450 = $18

That 4% has been paid in 1/2% increments (one increment every 7 days), so there have been 8 payments so far.

(8)(7 days) = 56 days

Final Answer: E

GMAT assassins aren't born, they're made,
Rich

I have one doubt.. he started to pay after 7 days.. so shouldn't the days 56+7?

Think of it this way:

Payment 1 happens on day 7.
Payment 2 happens on day 14 (or 2*7)
Payment 8 happens on day 56 (or 8*7)

I understood what you said, but my doubt was that he started to pay after 7 days of amount disbursed. After 7 days, he started to pay every 7 days. So shouldn't the first payment after 14 days?

I see. This could have been worded a little more clearly. When we see If he pays back .5% of the total amount every 7 days,beginning exactly 7 days after the loan was disbursed what it means is If he pays back .5% of the total amount every 7 days, and the first payment occurs 7 days after the loan was disbursed

[[email protected]]

Hi Akashdeep13,

When working through GMAT questions, the answer choices sometimes provide helpful 'clues' as to how you can go about solving the given question. In that same way, they can sometimes help you to properly interpret what the question is saying.

You bring up an interesting interpretation of the wording of the prompt, BUT since THAT answer (re: 63) is not among the 5 choices, that interpretation CANNOT be correct.

GMAT assassins aren't born, they're made,
Rich

[Matt@VeritasPrep]

I understood what you said, but my doubt was that he started to pay after 7 days of amount disbursed. After 7 days, he started to pay every 7 days. So shouldn't the first payment after 14 days?

When in doubt, use the common sense interpretation. "Beginning" here should imply when the first payment was made, not when the seven day window initiates. It would be the same with a 0% interest credit card (e.g. payments "begin" 12 months after you receive the card).