I got sick of doing the math every year, so I made a table for large batches of strawberry jam. The recipe is based on using Certo liquid pectin.

Certo Pectin Pouches	Strawberries Pounds	Strawberries Hulled and crushed cups	Sugar cups	Sugar Ounces	Sugar Pounds	Yield Pints
1	4	4	7	49	3.066	4
2	8	8	14	98	6.132	8
3	12	12	21	147	9.198	12
4	16	16	28	196	12.264	16
5	20	20	35	245	15.33	20
6	24	24	42	294	18.396	24
7	28	28	49	343	21.462	28
8	32	32	56	392	24.528	32