Set this up with a direct formula instead of working step by step through the meq totals. Gypsum requirement, in meq per 100 gm of soil, can be written as:
\[GR = \frac{(C_1 - C_2) \times V}{W} \times 100\]
where \(C_1\) is the starting calcium concentration of the gypsum solution in meq/l, \(C_2\) is the Ca+Mg concentration found in the filtrate in meq/l, \(V\) is the volume of solution used in litres, and \(W\) is the weight of soil in grams.
Substitute the given numbers: \(C_1 = 36\), \(C_2 = 32\), \(V = 0.1\) litre, \(W = 5\) gm.
\[GR = \frac{(36-32)\times 0.1}{5}\times 100 = \frac{4 \times 0.1}{5}\times 100 = \frac{0.4}{5}\times 100 = 8\]
The formula gives the same result as the step by step method, 8 meq of gypsum needed per 100 gm of this alkali soil.
\[\boxed{8\ \text{meq}/100\text{gm soil}}\]