In the table above is shown the percent reduction in the

interesting question..

i think i will choose A for this... only statement 1 is sufficient...

how i solved?
B - of course is sufficient.. $202.50 .. falls under 3rd category BUT i dont know which day in 3rd category.. it can be any from july 15th through 21st...

now for A to be correct there is hint... to see if 55% of 450 - 30% of 450 = 112.50 and i think it is.
so it is the 15th day of july

Fluke is right. This is a typical DS trap. If we see that a difference of 112.50 show up at the junction of two date ranges, we figure we have the answer and start congratulating ourselves. However, it's really important to check and see if there is more than one junction where that particular difference shows up. Assume that there will be, and you can be pleasantly surprised if you're wrong!

(1) insuff..because we don't know the discounted price/any price for which he would have paid $112.5.
(2)202.5 is what percent less of 450...
450(1-x/100)=202.5
x=55%
date "n" could be anything between july15-july21...not suff....

Combining both Bill paid $112.50 less than he would have if he had bought it the day before
means bill paid (202.5+112.5=$315) if he bought with any previous discount a day before.
315 is 30% less than 450.
So he must bought on july 15
Ans C

Algebraic approach:

Statement 1
Let \(x\) be the discount Bill received and let \(y\) be the previous period's discount. So we get this equation:
\(450(1-x) = 450(1-y) - 112.50\)
Which reduces to:
\(x-y = 0.25\)
This means that in the previous period, the discount was 25% less. Thus, Bill either bought his suit on July 8 or July 15. July 1 is not possible because there was no discount the day before. And July 22 is not possible because the discount was 15% less the day before.
Not sufficient.
Note that if the equation reduced to \(x-y = 0.15\), Statement 1 alone would have been sufficient.

Statement 2
\(202.50 = 450(1-x)\) where \(x\) is the discount Bill received.
\(x = 0.55\)
So Bill could have bought his suit on any day July 15 through July 21.
Not sufficient.

Combining both statements
In Statement 1, we narrowed down the answer to July 8 or July 15.
In Statement 2, we narrowed down the answer to July 15 through July 21.
The only date common do both is July 15.
Sufficient.

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