gmatprep - sets problem

[shahab03]

please explain your solution..
thanks


when 1,000 children were inoculated with a certain vaccine, some developed inflammation at the site of the inoculation and some developed fever. How many of the children developed inflammation but not fever ?

(1) 880 children developed neither inflammation nor fever
(2) 20 children developed fever.

[hengirl03]

I tried to solve this problem by filling out a table. However, it couldn't fill the table completely. So I think the answer is E. What is the official answer?

[arorag]

Ans should be C

draw venn diagram

[hengirl03]

Would you explain how you got C please?

Is it:

There 120 students w/ fever or inflammation.
20 of those student have the only fever or the fever w/ inflammation.
So, 100 of the students have only inflammation.

[parallel_chase]

please explain your solution..
thanks


when 1,000 children were inoculated with a certain vaccine, some developed inflammation at the site of the inoculation and some developed fever. How many of the children developed inflammation but not fever ?

(1) 880 children developed neither inflammation nor fever
(2) 20 children developed fever.

Answer should be C

Inflammation - I
Fever - F

Total = F + I - Both (I+F) + Neither (I+F)

I - Both (I+F) = ???

Statements 1 & 2 are clearly insufficient alone.

Combining 1 & 2

1000 = 20 + I - Both (I+F) + 880

I - Both (I+F) = 100

Sufficient.

Hence C is the answer.

[ddm]

To parallel_chase

2nd statement mentions that 20 children developed fever...but it is even possible that few out of 20 even developed inflammation...

N the question is asking How many of the children developed inflammation but not fever.

I - Both (I+F) = 100
This does not answer the question

[Sunny22uk]

To parallel_chase

2nd statement mentions that 20 children developed fever...but it is even possible that few out of 20 even developed inflammation...

N the question is asking How many of the children developed inflammation but not fever.

I - Both (I+F) = 100
This does not answer the question

You are right it is quite possible that few out of 20 even developed inflammation. The question asks How many of the children developed inflammation but not fever ? If 20 of them developed fever,they can be subtracted

[greentealeaf]

To parallel_chase

2nd statement mentions that 20 children developed fever...but it is even possible that few out of 20 even developed inflammation...

N the question is asking How many of the children developed inflammation but not fever.

I - Both (I+F) = 100
This does not answer the question

NOT FEVER is important. don't confuse it with Inflammation.