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Finding the Fourth Proportional to 420.90, 582.30 and 369.30

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Solution

The fourth proportional to 420.90, 582.30 and 369.30 is: 510.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.90 : 582.30 = 369.30 : x
  2. Step 2: Convert to fraction form
    420.90/582.30 = 369.30/x
  3. Step 3: Cross multiply
    420.90x = 582.30 × 369.30
  4. Step 4: Simplify right side
    420.90x = 215,043.39
  5. Step 5: Solve for x
    x = 215,043.39/420.90
  6. Step 6: Final answer
    x = 510.91

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.