Solve Simplify the Answer $1 \frac { 4 } { 5 }$

Multiple Choice

Solve. Simplify the answer.
-Brian was training to run a marathon. During the three-day period before the race he decided that he would train for a total of 9 hours. If he trained for $1 \frac { 4 } { 5 }$ hours on the first day and $3 \frac { 9 } { 10 }$ hours on the second day, how many hours would he need to train on the third day?

A) $3 \frac { 7 } { 10 } \mathrm { hr }$
B) $3 \frac { 2 } { 5 } \mathrm { hr }$
C) $4 \frac { 3 } { 10 } \mathrm { hr }$
D) $3 \frac { 3 } { 10 } \mathrm { hr }$