It takes Johnson 10 minutes to walk to the car park and 20 min to drive to work. At what time should he get out of the house in order to get to work at 9:00 a.m.?
Select
A) 8:50 a.m	B) 5:50 a.m	C) 7:50 a.m	D) 6:50 a.m	E) 8:30 a.m
The time it takes Johnson to get to work: time to walk to car park + time to drive     10 + 20= 
<gadget id="calculator">  10 + 20</gadget>
<output>30</output>
30 minutes   Johnson needs to get out of the house 30 minutes before 9:00 am at   9:00 - 0:30= 8:30 a.m   correct answer 8:30 a.m
<result>E</result>
It takes Johnson 10 minutes to walk to the car park and 20 min to drive to work. At what time should he get out of the house in order to get to work at 9:00 a.m.?