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Finding the Third Proportional to 428.91 and 555.47

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Solution

The third proportional to 428.91 and 555.47 is: 719.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.91 : 555.47 = 555.47 : x
  2. Step 2: Convert to fraction form
    428.91/555.47 = 555.47/x
  3. Step 3: Cross multiply
    428.91x = 555.47 × 555.47
  4. Step 4: Simplify right side
    428.91x = 308,545.53
  5. Step 5: Solve for x
    x = 308,545.53/428.91
  6. Step 6: Final answer
    x = 719.38

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Why These Related Problems?

These problems maintain the same ratio (1.30) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.