A woman has m $20 notes and n $50 notes. The total amount of money in her possession cannot be less than $800. Represent this as an inequality.
20m+50n≥800
Total value of m $20 notes and n $50 notes = 20m + 50 n
The least amount of money the woman can have in her possession is $800.
Therefore, 20m+50n≥800
The correct choice is D.