Step 1 :\[\text{1. Calculate total paper clips:}\]
Step 2 :\[3 \times \frac{7}{8} = \frac{21}{8}\]
Step 3 :\[\text{2a. Calculate Gabe's work time:}\]
Step 4 :\[5 \frac{1}{3} \times \frac{5}{4} = \frac{16}{3} \times \frac{5}{4} = \frac{80}{12} = 6 \frac{2}{3}\]
Step 5 :\[\text{2b-c. Calculate Paula's work time:}\]
Step 6 :\[5 \frac{1}{3} \times \frac{3}{4} = \frac{16}{3} \times \frac{3}{4} = \frac{48}{12} = 4\]
Step 7 :\[\text{3. Calculate basement length (L) and width (W):}\]
Step 8 :\[\text{Area = Length (L) x Width (W), with } W = \frac{2}{3}L \text{, so:}\]
Step 9 :\[864 = L \times \left(\frac{2}{3}L\right)\]
Step 10 :\[L^2 = \frac{3}{2} \times 864\]
Step 11 :\[L^2 = 1296 \Rightarrow L = \sqrt{1296} \Rightarrow L = 36\]