How may scanes of yarn?

It's "skeins".

It is impossible to tell you how much you need. You need to make your gauge swatch and then you will know. Make a square out of a known quantity of yarn and them measure it. Then you can calculate how much you will need for something much larger. You can also weigh it and then you will know the weight of the total yarn. But it all depends on the kind of yarn you are using (not all yarn weighs the same, you know) and what tension you crochet at.... this is all very personal, and MY figures will not be the same as yours.

It's going to be a tight stitch with that needle. If you are using

just one color 10 skeins should work. Use the red heart at

Walmart . If you use the big skeins and one color you may

not need that many. Buy them. You can always take back

what you don't use. Walmart is good about that. Simply

soft yarn is nice too and you can find that at Michaels.It

makes a soft afghan. Then you will need 10 or 12 skeins.

One thing you also need to keep in mind is that even though it says "no dye lot" on the wrapper the colors do differ. Your best bet if you don't want to do the math is pick a couple different colors so that if you have to get more and the shade doesn't match it won't show as much being separated. When getting your yarn you will want to hold several skeins together and go to a part of the store with stronger light to check and see if the shades match.

I am not sure as I don't know how much your getting in your gauge. And it's going to require some algebra to figure up how much yardage your going to need for that size blanket by your gauge. If you use Red Heart (as poster above suggested) your going to be ok with going back and getting that yarn since there are no dye lots. I would personally grab 5 or 6 skeins to start with and go from there.

Yarn weight of 4 doesn't tell me anything at all, are you refering to 4 ply?? Plys don't count much in the size of yarn.

Since I think you are refering to Worsted Weight yarn this comes in SKEINS of 4-ounce.

It will be about 10 or 12 4-ounce skeins or about 40 to 48 ounces of yarn.

I use RedHeart yarns when designing afghans, because there is no "Dye Lot Number" on their colors, and also because the Super Saver Skeins come in 8-oz and 16-oz size skeins.

it depends on what your gauge is, and the stitch that you use.

what i do is buy at least 1000 yards to start out with and then buy more as i need it.