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Finding the Fourth Proportional to 389.00, 583.54 and 128.93

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Solution

The fourth proportional to 389.00, 583.54 and 128.93 is: 193.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.00 : 583.54 = 128.93 : x
  2. Step 2: Convert to fraction form
    389.00/583.54 = 128.93/x
  3. Step 3: Cross multiply
    389.00x = 583.54 × 128.93
  4. Step 4: Simplify right side
    389.00x = 75,232.57
  5. Step 5: Solve for x
    x = 75,232.57/389.00
  6. Step 6: Final answer
    x = 193.40

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.