consider the following simplex tableau being used to maximize z. the current solution is not optimal and…

consider the following simplex tableau being used to maximize z. the current solution is not optimal and needs at least one more pivot operation to complete the method.\n\n(a) which variable is the entering variable?\n\n(b) calculate the ratios, entered as decimals rounded to two decimal places:\n(enter dne in the last column if the ratio is not positive.)\n\n(c) which variable is the exiting variable?

consider the following simplex tableau being used to maximize z. the current solution is not optimal and needs at least one more pivot operation to complete the method.\n\n(a) which variable is the entering variable?\n\n(b) calculate the ratios, entered as decimals rounded to two decimal places:\n(enter dne in the last column if the ratio is not positive.)\n\n(c) which variable is the exiting variable?

Answer

Answer:

(A) (x_{2}) (B)

Row Variable Ratio as Decimal
Row 1 (s_{1}) (65.33)
Row 2 (s_{2}) (22.00)
Row 3 (s_{3}) (DNE)
(C) (s_{2})

Explanation:

Step1: Determine the entering variable

In the simplex method for maximization, we look at the bottom - row (the (Z) - row excluding the (Z) - value). The most positive coefficient in the non - basic variable columns ((x_1,x_2,x_3)) determines the entering variable. The coefficients of (x_1,x_2,x_3) in the (Z) - row are (- 3,1,0). Since (1) (the coefficient of (x_2)) is the most positive, the entering variable is (x_2).

Step2: Calculate the ratios

The ratio for a row (i) is calculated as (\frac{\text{Right - hand side value of row }i}{\text{Entry in the entering variable column of row }i})

  • For Row 1: The right - hand side value is (196) and the entry in the (x_2) column is (3). The ratio is (\frac{196}{3}\approx65.33), and the variable in Row 1 is (s_{1}) (the slack variable corresponding to the first constraint)
  • For Row 2: The right - hand side value is (66) and the entry in the (x_2) column is (3). The ratio is (\frac{66}{3}=22.00), and the variable in Row 2 is (s_{2}) (the slack variable corresponding to the second constraint)
  • For Row 3: The entry in the (x_2) column is (2), but we consider non - negative ratios. Since we are maximizing, we ignore non - positive ratios. The right - hand side value is (151) and the entry in the (x_2) column is (2) (but we use the formula (\frac{\text{RHS}}{\text{Entry in entering variable column}}). However, if we consider the standard simplex ratio calculation for maximization (non - negative ratios), for the third row, if we assume the formula (\frac{151}{2} = 75.5), but looking at the simplex tableau structure (the original problem's constraints), we should use the correct columns. Wait, no, re - checking: The correct formula for the ratio is (\text{Ratio}=\frac{b_i}{a_{ij}}) where (b_i) is the right - hand side of the (i) - th row and (a_{ij}) is the entry in the (j) - th column (entering variable column) of the (i) - th row. For Row 3: The entry in the (x_2) column is (2) (assuming it's a typo in the problem statement's tableau, if we follow the ratio rule for maximization (non - negative ratios for non - negative (a_{ij})). But actually, in the simplex tableau for maximization, we calculate (\frac{b_i}{a_{ij}}) for (a_{ij}>0). The right - hand side of Row 3 is (151) and the entry in the (x_2) column (entering variable) is (2). But wait, no, looking at the tableau: The first three rows are constraint rows. The right - hand side values are (196) (Row 1), (66) (Row 2), (151) (Row 3). The entries in the (x_2) column (entering variable) for Row 1: (3), Row 2: (3), Row 3: (2). But in maximization simplex, we calculate (\frac{b_i}{a_{ij}}) for (a_{ij}>0). However, if we consider the standard ratio test (to find the smallest non - negative ratio), but actually, we made a mistake above. Wait, no, re - looking at the simplex tableau: The bottom row ( (Z) - row) has coefficients for (x_1,x_2,x_3,s_1,s_2,s_3) as (-3,1,0,0, - 2,0). The entering variable is (x_2) (since (1) is the most positive in the non - basic variable columns ((x_1,x_2,x_3))). For the ratio calculation: Row 1: (\frac{196}{3}\approx65.33) (variable (s_1)) Row 2: (\frac{66}{3} = 22.00) (variable (s_2)) Row 3: The entry in the (x_2) column is (2), but if we assume the correct formula (\frac{\text{RHS}}{a_{ij}}), but in the context of the simplex method (maximization), we consider non - negative ratios. However, if we look at the original problem (assuming the tableau is set up correctly), the third row's right - hand side is (151) and (a_{ij} = 2) (for (x_2)), but actually, no, we made a mistake. Wait, no, the first three rows are: Row 1: (6x_1+3x_2 + 0x_3+s_1+0s_2+0s_3=196) Row 2: (7x_1 + 3x_2+0x_3+0s_1 + 2s_2+1s_3=66) Row 3: (3x_1+2x_2+1x_3+0s_1+3s_2+0s_3=151) The ratio for Row 1: (\frac{196}{3}\approx65.33) ( (s_1) is the basic variable) The ratio for Row 2: (\frac{66}{3}=22.00) ( (s_2) is the basic variable) The ratio for Row 3: (\frac{151}{2}=75.5), but wait, no, in the simplex method, when we have (a_{ij}) (entry in entering variable column) positive, we calculate the ratio. But if we consider the standard ratio test (to find the smallest non - negative ratio). The smallest non - negative ratio is (22.00) (from Row 2)

Step3: Determine the exiting variable

The exiting variable is the basic variable corresponding to the row with the smallest non - negative ratio. Since the smallest non - negative ratio ((22.00)) is in Row 2 and the basic variable in Row 2 is (s_{2}), the exiting variable is (s_{2})