In a certain district, the ratio of the number of registered Republicans to the number of registered Democrats was 3/5. After 600 additional Republicans and 500 additional Democrats registered, the ratio was 4/5. After these registrations, there were how many more voters in the district registered as Democrats than as Republicans?  Choose the correct choice from the following answers:
A) 100 B) 300 C) 400 D) 1,000 E) 2,500
3/5= 
<gadget id="calculator">3/5</gadget>
<output>3/5 = around 0.6</output>
0.6*x   Another 600 register as republican, with the total amount being 80% republican (4/5)   Total new voters is 1,100 (500+600)   So, 0.6x + 600= 0.8(x+1,100)   0.6x + 600 = 0.8x + 880   answer is 300
<result>B</result>
In a certain district, the ratio of the number of registered Republicans to the number of registered Democrats was 3/5. After 600 additional Republicans and 500 additional Democrats registered, the ratio was 4/5. After these registrations, there were how many more voters in the district registered as Democrats than as Republicans?