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Finding the Fourth Proportional to 538.61, 808.65 and 428.99

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Solution

The fourth proportional to 538.61, 808.65 and 428.99 is: 644.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.61 : 808.65 = 428.99 : x
  2. Step 2: Convert to fraction form
    538.61/808.65 = 428.99/x
  3. Step 3: Cross multiply
    538.61x = 808.65 × 428.99
  4. Step 4: Simplify right side
    538.61x = 346,898.72
  5. Step 5: Solve for x
    x = 346,898.72/538.61
  6. Step 6: Final answer
    x = 644.07

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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.