The fourth math problem in the third grade of primary school is urgent. Thank you.

12 lines per day, and 12×7=84 lines per week, totaling *** 100 lines, and 100 lines > 84 lines, so embroidery can't be finished in one week. There are lines 100-84= 16, 16÷ 12= 1 (days) ... 4 (lines), so it will take another 2 days. —— Chenxi Education Trustee will answer for you.