Cast on How Many?

I would say I’m an intermediate knitter, but am making my first sweater. I am looking at two different patterns and while they are both very basic I am confused about how many stitches I’m supposed to cast on.
For a 48" bust measurement one tells me to cast on 48 stitches. The other gives me the elusive measurement of:
3sts= 1" (chart sizes I don’t need) 48" 950
Is that 950 stitches? because in my estimate if 3 stitches equal 1" then 48" is 144 stitches.
I hope one of you lovely people can help me because I can’t get back to the knitting store for at least a week, and I’m really sick of knitting my holiday presents day in and day out.

Bright Blessings, Hilary

Can you give us a link to the pattern or patterns please?

I don’t have links for the patterns because they are real paper copies, one I bought in a knitting store and the other came in a book I bought. I took pictures of the area that I’m having trouble with, but I’m not seeing anywhere that I can attach files too. I am so sorry about this, I’m not much of a computer person and this is the first forum I’ve ever joined.

Okay, a pattern name will help. Never post a whole pattern, but a picture would be okay. You can attach by clicking onthe paper clip, but you may need to resize the pic first.

The pattern should tell you how many to cast on. It’s usually at the beginning of the instructions.