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Finding the Fourth Proportional to 420.10, 630.55 and 359.30

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Solution

The fourth proportional to 420.10, 630.55 and 359.30 is: 539.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.10 : 630.55 = 359.30 : x
  2. Step 2: Convert to fraction form
    420.10/630.55 = 359.30/x
  3. Step 3: Cross multiply
    420.10x = 630.55 × 359.30
  4. Step 4: Simplify right side
    420.10x = 226,556.62
  5. Step 5: Solve for x
    x = 226,556.62/420.10
  6. Step 6: Final answer
    x = 539.29

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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.