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Finding the Fourth Proportional to 430.29, 645.54 and 137.79

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Solution

The fourth proportional to 430.29, 645.54 and 137.79 is: 206.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.29 : 645.54 = 137.79 : x
  2. Step 2: Convert to fraction form
    430.29/645.54 = 137.79/x
  3. Step 3: Cross multiply
    430.29x = 645.54 × 137.79
  4. Step 4: Simplify right side
    430.29x = 88,947.53
  5. Step 5: Solve for x
    x = 88,947.53/430.29
  6. Step 6: Final answer
    x = 206.72

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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.