Sati and Savitri visited three temples to offer flowers At the first

Question

Sati and Savitri visited three temples to offer flowers At the first temple, Sati offered two-third of her flowers, plus one extra flower. At the second temple also she offered two-third of her flowers, and an extra flower. After repeating the process at the third temple, she was left with one flower. Savitri started with the same number of flowers as Sati. but offered 20 flowers at each temple How many flowers did Savitri have left after visiting the third temple?

A 0
B 6
C 12
D 36
E 66

A 0
B 6
C 12
D 36
E 66

chetan2u · Accepted Answer

Let’s act backwards.

Sati 
Third time: Left=1, so A-((2A/3)+1)=1…..A/3=2…..A=6
Second time: Left=6, so B-((2B/3)+1)=6…..B/3=7…..B=21
First time: Left=1, so C-((2C/3)+1)=21…..C/3=22…..C=66

Savitri 
All three temples: 20 each, so 3*20 or 60 flowers used. 
Left = 66-60 = 6

B

playthegame · Answer

Thanks wow very elegant solution, how did you get to know that you had to work backwards? I am going to move into word problems now after focussing on algebra and arithmetic so I think working backwards on some of them will be a great strategy.

Thanks again,

onlyPlanA · Answer

Did this question become "hard" because in the statement: "At the second temple also she offered two-third of her flowers, and an extra flower", the word "remaining" was missing? Ideally, it should be "At the second temple, she offered two-third of her  remaining  flowers, and an extra flower."

KarishmaB · Answer

After the third temple, she had 1 flower left.

At the third temple, she gave away 1 flower so she must have had 2 flowers before. She also gave away 2/3rd of what she had at the beginning of third temple so these 2 flowers would be 1/3rd of what she had at the beginning of third temple. Hence she had 3 times i.e. 2*3 = 6 flowers at the beginning of third temple. 
Similarly, she had (6 + 1)*3 = 21 flowers at the beginning of second temple. 
and (21+1)*3 = 66 flowers at the beginning of first temple.

Had she given away 20 at each temple, she would be left with 66 - 3*20 = 6 flowers.

Answer (B)

egmat · Answer

Hi onlyPlanA,

Good eye on the wording, and you're right that adding  "remaining"  would read more cleanly. But here's the reassuring part: the sentence isn't actually ambiguous, because only one reading is mathematically possible.

Look at how chetan2u set it up. At each temple he treated "two-third of her flowers" as  two-thirds of what she is holding at that moment  - i.e., her remaining flowers. That's the reading you suspected, and it's the only one that works.

Why the other reading collapses immediately

Suppose "her flowers" meant two-thirds of her  original  66  every time.

- At the first temple she'd offer (2/3)( 66 ) +  1  =  45 , leaving  21 .
- At the second temple she'd again need to offer (2/3)( 66 ) +  1  =  45  - but she only has  21  left.

You can't give away  45  flowers when you're holding  21 . So the "two-thirds of the original pile" interpretation breaks on the very next step. The phrase  has  to mean "two-thirds of what she currently has," exactly as the backward solution assumed.

So the missing word doesn't create a real fork in the meaning - the numbers force the intended reading. The actual source of difficulty here isn't the phrasing; it's that the cleanest route is to  work backwards  from the  1  flower she ends with, since each temple's leftover depends on the one before it.

Bottom line: trust the interpretation chetan2u used - it's the only consistent one - and the answer stays  B .

Answer: B

Sati and Savitri visited three temples to offer flowers At the first

Prep Toolkit

Top 5 GMAT Debrief Videos

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

GMAT Problem Solving (PS) Questions

­Sati and Savitri visited three temples to offer flowers At the first

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

More than Quant/Verbal Abilities: Speed vs. Accuracy

745 with Only Self-Prep and GMAT Club

From 555 to 765: 210-point Improvement

Perfect 805 Score Debrief by Julia

My Rewards

Sati and Savitri visited three temples to offer flowers At the first