Getting the SUM of a range of cells with formulas

[desnyder2001]

I need a way to have a cell be NULL if it is Sat or Sun
I did find a formula to do this, but then it won't SUM the row and/or column

Site	US1787377	Wed	Thu	Fri	Sat	Sun	Mon	Tue	Wed	Thu	Fri	Sat	Sun	Mon	Tue	Wed	Thu	Fri	Sat	Sun	Mon	Tue	Wed	Thu	Fri	Sat	Sun	Mon	Tue	Wed	Thu	Fri				Monthly Billable
1	2	3	4	5	6	7	8	9	10	11	12	13	14	15	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31	Required	Actual	Difference
Supervisor		8	8	8			8	8	8	8	8			8	8	8	8	8			8	8	8	8	8			8	8	8	8	8	184.00	184.00	0.00	$ 6,152.96
Interior		24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	23.5	24	24	24	24	24	24	743.50	743.50	0.00	$ 19,026.17
Interior		24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	24	744.00	744.00	0.00	$ 19,038.96

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