How far can my NetGear wireless modem be from the wireless adapter before it won't work anymore?

I'm trying to hook a third computer in my garage on my wireless network.The wireless modem is set up for up to 4 computers. My garage is about 80 yards away, Is that just to far?How far can my NetGear wireless modem be from the wireless adapter before it won't work anymore?
most b wireless signals can reach up to 300 ft with no obstructions. since you going to pass signal through at least one wall the distance will decrease. The best way to know is just to try it. The g and n wireless signals will travel farther but the cost more.How far can my NetGear wireless modem be from the wireless adapter before it won't work anymore?
On the back , bottom or even in the box (instructions) of the wireless modem should have the range. Remember it varies depending on the range of the wireless modem.