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Finding the Fourth Proportional to 430.74, 645.25 and 199.31

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Solution

The fourth proportional to 430.74, 645.25 and 199.31 is: 298.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.74 : 645.25 = 199.31 : x
  2. Step 2: Convert to fraction form
    430.74/645.25 = 199.31/x
  3. Step 3: Cross multiply
    430.74x = 645.25 × 199.31
  4. Step 4: Simplify right side
    430.74x = 128,600.55
  5. Step 5: Solve for x
    x = 128,600.55/430.74
  6. Step 6: Final answer
    x = 298.56

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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.