Rachel needs to type up her 1950-word paper by its 5 pm deadline. If she starts at least two hours in advance, her typing speed will be a constant 20 words per minute, but for every two minutes beyond 3:00 PM that she waits before starting, her constant typing speed will increase by one word per minute. What is the latest time at which Rachel can begin typing in order to finish her paper by the deadline?
Why does 1950/20 approximately equals 100 implies A and B are eliminated first?
A. 2:50 pm
B. 3: 23 pm
C. 3: 30 pm
D. 4: 30 pm
E. 4: 42 pm
Beginning at $3:00\,\, (120\,min)$ requires $16.25\,\,wpm$ and she types at $20\,\,wpm.\quad$
Beginning at $3:30\,\, (90\,min)$ requires $21.67\,\,wpm$ and she types at $35\,\,wpm.\quad$
Beginning at $4:00\,\, (60\,min)$ requires $32.5\,\,wpm$ and she types at $50\,\,wpm.\quad$
Beginning at $4:30\,\, (30\,min)$ requires $65\,\,wpm$ and she types at $65\,\,wpm.\quad$