Sophia is buying a smartphone and a phone charger at an electronics

Question

Sophia is buying a smartphone and a phone charger at an electronics store for a total price of $630. This price reflects a discount from the original prices of both devices due to a sale the store is offering. Assuming no taxes or other fees are involved, what was the original price of the phone charger alone?

(1) The sale that the store is offering is 15 percent off a total purchase of $500 or more or 20 percent off a total purchase of $800 or more.

(2) The original price of the smartphone alone was $720.

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Sketchitesh · Answer

S + C = Original Price Final Price = OP* (1- Discount) = 630 Question => C = ? 1. If 500 =< OP < 800 then Discount= 15% Assuming this case then OP = FP/(1-discount) => 630/(1-0.15)= 741 If 800 =< OP then Discount= 20% Assuming this case then OP = FP/(1-discount) => 630/(1-0.2)= 787 <800 (reject this case) S + C = 741 (Not sufficient) 2. S = 720 (Not sufficient) Together, Sufficient. (2 eq. 2 unk.) C is the answer

Dereno · Answer

Sophia is buying a smart phone and phone charger for $630 ( price after discount).

Assuming no taxes or other fees are involved, We need to find the price of phone charger.

We need to find price of phone charger.

Statement 1:

(1) The sale that the store is offering is 15 percent off a total purchase of $500 or more or 20 percent off a total purchase of $800 or more.

Case A: Store offers a discount of 15% for purchase greater than $500.

(S+P) * 85/100 = $630

(S+P) = $741.17

This is less than 800.

since , we don’t know the price of S or P. We cannot calculate P.

NOT SUFFICIENT

Case B:

Store offers a discount of 20% for purchase $800 or more.

(S+P) *80/100 = $630

(S+P) = 787.5. Neglecting this case . Because, the purchase is lesser than $800.

THIS CASE IS ELIMINATED.

Statement 2: 
  
(2) The original price of the smartphone alone was $720.

The statement S + P = $630 , which is after discount.

Hence,  NOT SUFFICIENT .

Let’s Combine statements 1 and 2,

from statement 1, we get (S+P) = $741.17

from statement 2, we get S = $720

then, P = $741.17 - $720 =  $21.17

price of phone charger is $21.17.

Option C

ManifestDreamMBA · Answer

Let original cost of phone be  P , charger be  C  and discount be  D 
(P+C)(1-D) = 630
C = ?

Statement 1
If cost were 800, then after 20% discount, it would have costed atleast 640
This means total cost was less than 800 and discount received is 15%
However this doesn't tell me individual prices of phone or charger 
Insufficient

Statement 2
P = 720
We don't know anything about D to calculate C
Insufficient

Combined, we have P = 720 and D = 0.15
(720+C)(1-0.15) = 630
Can be solved to calculate C

Answer C

Shwetabh54 · Answer

When we combine statement 1 & 2 then there is two possibilities.

1st - Phone charger cost > $80, in this case 20% discount will be applicable (Total cost will exceed $800)
2nd - Phone charger cost < $80, in this case 15% discount will be applicable (Total cost will be less than $800)

While solving 1st, we get the price of charger as $ 67.5. Which is contradicting the assumption (Cost > $80). Hence eliminated.
While solving 2nd, we get the price of charger as $ 21.17. Which is acceptable according to the assumption (Cost < $80). Accepted.

Hence C is the correct answer.

I saw two possibility and hence thought I will get two answers (without solving the condition), marked E and got trapped

Sophia is buying a smartphone and a phone charger at an electronics

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GMAT Data Sufficiency (DS) Questions

Sophia is buying a smartphone and a phone charger at an electronics

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