What is the difference between the total numbers of projects handled by company A in 2003 and 2004 together and the total number of projects handled by company B in 2005 and 2007 together?

Answer: Option B

The number of projects handled by company A in 2003 and 2004 together
= 180 + 230
= 410
The number of projects handled by company B in 2005 and 2007 together
= 210 + 350
= 560
Required difference
= 560 - 410
= 150