answer should be 425000 but need it explained well. thank you.

5) Chang Corporation has two divisions, T and W. The company's overall contribution margin ratio is 40%, with sales in the two divisions totaling $900,000. If variable expenses are $200,000 in Division T and if Division W's contribution margin ratio is 20%, the sales in Division W must be: A) $200,000 B) $425,000 C) $700,000 D) $340,000