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Finding the Fourth Proportional to 419.61, 628.73 and 256.83

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Solution

The fourth proportional to 419.61, 628.73 and 256.83 is: 384.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.61 : 628.73 = 256.83 : x
  2. Step 2: Convert to fraction form
    419.61/628.73 = 256.83/x
  3. Step 3: Cross multiply
    419.61x = 628.73 × 256.83
  4. Step 4: Simplify right side
    419.61x = 161,475.44
  5. Step 5: Solve for x
    x = 161,475.44/419.61
  6. Step 6: Final answer
    x = 384.82

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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.