Help with reading pattern punctuation

How-to Questions
1

Hi I need some help with interpreting a pattern for a jacket. Specifically for shaping arm hole. Here it is: Dec 1 st at armhole edge of next 5(5:7:7:9:9:10:10] rows, then on foll 1(1:0:0:0:0:0:0) alt rows. 44(45:46:49:50:52:55:57) sts. Work 1(1:1:1:1:1:0:0) row, ending with RS facing for next row.

Should I decrease one stitch at arm whole only on knit rows and alt rows nothing (note I’m the largest size)? Or do I fully finish those 10 rows decreasing both knit and purl rows at same time for 10 rows?

Thanks for help

2

Welcome to the forum!
Decrease on [I]every[/I] row, both knit and purl rows, at the armhole edge.

3

Thank you so much!