GMAT Data Sufficiency Question 08: Overlapping sets/Venn diagrams

 
The following GMAT data sufficiency question tests your understanding of how to deal with overlapping sets using Venn diagrams or other approaches.

Question 8:

At a certain company with 90 employees, 70 have cell phones and 60 have laptops. How many employees do not have either a cell phone or a laptop?

1. (1) The number of employees that have cell phones only is twice the number of employees that have laptops only.
2. (2) 80 employees have either a cell phone or a laptop.

1. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
2. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
3. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
4. EACH statement ALONE is sufficient.
5. Statements (1) and (2) TOGETHER are NOT sufficient.