The starting simplex table of a linear programming problem is given below, where \( S_1, S_2, S_3, S_4 \) are the slack variables. The objective of the problem is
Maximize \( z = 6x_1 + 4x_2 \)
The leaving variable among the basic variables is:

In the simplex method, the objective is to identify the leaving variable in the basic feasible solution. The leaving variable is determined by the minimum ratio test. This test helps identify which basic variable will be replaced by the non-basic variable in the next iteration. We need to check the minimum positive ratio of the solution values to the corresponding coefficients in the \( x_1 \) column.
The ratios are calculated as follows:
- For \( S_1 \): \( \frac{36}{6} = 6 \)
- For \( S_2 \): \( \frac{40}{2} = 20 \)
- For \( S_3 \): \( \frac{2}{-1} \) (Negative value, not considered)
- For \( S_4 \): \( \frac{3}{0} \) (Not valid, as division by zero is undefined)
From these calculations, the minimum positive ratio is 6, which corresponds to \( S_1 \). Therefore, the leaving variable is \( S_1 \), which is option (A).
The hole and the shaft dimensions (in mm) are given as
Hole dimension = \(30 \pm 0.04\) and Shaft dimension = \(30 \pm 0.06\).
The maximum possible clearance (in mm) is .......... (Rounded off to two decimal places)
A through hole of 10 mm diameter is to be drilled in a mild steel plate of 30 mm thickness. The selected spindle speed and feed for drilling hole are 600 revolutions per minute (RPM) and 0.3 mm/rev, respectively. Take initial approach and breakthrough distances as 3 mm each. The total time (in minute) for drilling one hole is ______. (Rounded off to two decimal places)
In a cold rolling process without front and back tensions, the required minimum coefficient of friction is 0.04. Assume large rolls. If the draft is doubled and roll diameters are halved, then the required minimum coefficient of friction is ___________. (Rounded off to two decimal places)