Usually when we have had an inch or more of rain in a single

Question

Usually when we have had an inch or more of rain in a single day, my backyard immediately has mushrooms and other forms of fungus growing in it. There are no mushrooms or fungus growing in my backyard.

Which of the following would logically complete an argument with the premises given above?
A) therefore, there has been no rain here in the past day
B) therefore, there probably has been no rain here in the past day
C) therefore, we have not had more than an inch of rain here in the past day
D) therefore, we probably have not had more than an inch of rain here in the past day
E) therefore, mushroom and fungus will be growing in my backyard tomorrow

go2venkat · Answer

Ans: (D)

The pattern seems to be : If P then Q. If NOT Q must not be P.

anandnk · Answer

(C) and (D) come close but (D) is better because the stem starts off with word  usually

srijay007 · Answer

D for sure
"probably" correctly refers to "usually" in the stem

SmashingGrace · Answer

I don't agree with D. One of the premises in the question is  'AN INCH or more' of rain  Fungi would start growing even if there was just one inch of rain, not necessarily more.

Based on that, I would choose B.

Vithal · Answer

Good point SmashG.. I missed it :ouch

I change my Answer to B :-)

Paul · Answer

OA is D
Start by the conclusion. It says that  there was no mushroom .

B) say you had .5 inch of rain and there were no mushroom, then B would not hold
D) would be true in any instances and matches the author's point

ob · Answer

D is the answer.

By negating the conclusion, the only thing we can assume is that we we have not had an inch or more of rain in a single day. Hence D.

SmashingGrace · Answer

I hate to be so thick, but can you explain the fine line between B & D.

To me, the premise says:

If rain EQUALS or MORE than 1 inch, then Mushrooms.

Now when I think of examples, I see three situations.

Situation #1: 1.5 inch of rain = mushrooms
Situation #2: 0.5 inch of rain = no mushrooms
Situation #3: EXACTLY 1 inch of rain = ???

D seems to assume that when there's EXACTLY 1 inch of rain ---> no mushrooms

B seems to assume that when there's EXACTLY 1 inch of rain ---> mushrooms

I feel I'm close to getting it, but not completely, even after reading all the comment.

enigmatic007 · Answer

that was Intresting very very.... may I explain: the sentence goes ''USUALLY ( now keep that in mind smshing) ! when there is an inch or MORe of rain.... X Y Z happens'' B) say ''thr was no rain PROBABLY'' then thr is a possibilty that thr MUST have been some rain... which If is truecompletely negates the given COCLUSION and that wud upset the author :oops:

D) say '' thr was PROBABLY not more than an INCH of rain Y'day'. ok.... may be thr was just .99 inch of rain or less'' whch still holds the coclusion ''strong'' aha! the author seems to be :-D

D does not seem to assume that when thr was an INCH of RAIN ...thr are NO mushrooms or watever! but what we got to keep in mind here is the senetcne says'' USUALLY'' which means when it rains USUALLY the mush rooms pop up and not NECCESSARILY'' AND d comes very close to supporting that ... hope that helps! and by chnace if this STIL doz not satisfy smashing( for which the probability is more so !...I m raedy for a smashing! Have Fun

SmashingGrace · Answer

Thanks for the explanation, enigmatic. I think I get it now.

Bhai · Answer

I selected B but understand now that D it is.

enigmatic007 · Answer

any time ... :-D

smashing . have fun

Makky07 · Answer

Also, the word "probably" in D makes the sentence much safer. There could be another explanation unknown to us that indicates that it has not rained more than an inch.

Usually when we have had an inch or more of rain in a single

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