Amanda Knits

If I knit 3 inches with 2 balls of yarn doubled, how much yarn will it take to make a sleeveless sweater 24 inches long, considering that after 5 inches of work I will start decreasing on both sides and after 15 inches of work, I will split for the armholes? And how much extra yarn did that crazy-intensive 415 stitch I-cord cast on (thus, over 1600 stitches) take and how many more rows can that account for for the rest of the sweater?

Shoot, how many balls it needs it moot since I have 9 left.

So. How do I make this work?

For the record: when designing a sweater designed to wrap across the front, the number cast on should actually be 1 and a half times the desired overall circumference of the sweater (wrapped closed).

It's a pain to realize this "duh" moment after you've already done an I-cord cast on and knit 2 and a half rows.