What is the probability that it will rain tomorrow ?

Our goal is to find the "What is the probability that it will rain tomorrow".

1) Prob. that it rains today =40/100=2/5
Prob. of not having rains today=1-2/5=3/5

2) If it rains today, the probability that it will rain tomorrow will increase by 10%
But the prob.that it rains today is tomorrow is still x.

If we combine both the statements ,This concludes to
prob. that rain today =2/5 and the prob. that it rains tomorrow =x+10%

Since the prob. that it will rain tomorrow is still unknown.

Answer E

Statement 1 - It only gives us the probability of raining today. However, we want to know the probability of rain tomorrow. Insufficient.
Statement 2- It says that if it rains today the probability of raining tomorrow will increase by 10%. But wait, we have no idea what is the probability of raining tomorrow.

Both statement combined together do not give the exact probability of raining tomorrow or probability of raining tomorrow if it rains today. Hence insufficient.

Answer is 'E'

I cant see the options

This is a data sufficiency question. Options for DS questions are always the same.

The data sufficiency problem consists of a question and two statements, labeled (1) and (2), in which certain data are given. You have to decide whether the data given in the statements are sufficient for answering the question. Using the data given in the statements, plus your knowledge of mathematics and everyday facts (such as the number of days in July or the meaning of the word counterclockwise), you must indicate whether—

A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked.
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked.
C. BOTH statements (1) and (2) TOGETHER are sufficient to answer the question asked, but NEITHER statement ALONE is sufficient to answer the question asked.
D. EACH statement ALONE is sufficient to answer the question asked.
E. Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed.

I suggest you to go through the following posts:
ALL YOU NEED FOR QUANT.
Ultimate GMAT Quantitative Megathread

Hope this helps.

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