1/3 yard = 1/2 hr
x yard = 1 hr
Okay, so if 1/3 of his yard is mowed in half an hour, "x" of his yard is mowed in an hour.
1/3 yard is to 1/2 hr as "x" yard is to 1 hr
Solve by cross multiplying:
1/2x = 1/3 *1
1/2x = 1/3
(divide both sides by 1/2)
2/3
Richard can mow 2/3 of his yard in one hour.
You can also figure this out by just realizing that 1/2 hr multiplied by 2 would give you 1 hr and then multiply 1/3 by 2 but it's good to get into the habit of solving things algebraically (or so I've been told).
