At a club 30% of members use both pool and sauna, 40% of members who use pool do not use saunA. What percentage of the members use the pool?

Let's break down the information given step by step:

Step 1: We know that 30% of members use both the pool and sauna.

Step 2: We also know that 40% of members who use the pool do not use the sauna.

Step 3: To find the percentage of members who use the pool, we need to consider the overlap between those who use both the pool and sauna and those who only use the pool.

Step 4: Since 40% of pool users do not use the sauna, we can subtract this percentage from the total percentage of members who use both the pool and sauna (30%).

Step 5: Therefore, the percentage of members who use only the pool can be calculated as follows:

Percentage of members who use only the pool = Percentage of members who use both pool and sauna - Percentage of pool users who do not use sauna = 30% - 40% = -10%

Step 6: However, a negative percentage does not make sense in this context. Therefore, we can conclude that there is an error in the given information or the question itself.

In summary, based on the given information, we cannot determine the percentage of members who use the pool accurately.