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Finding the Fourth Proportional to 538.10, 807.15 and 420.65

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Solution

The fourth proportional to 538.10, 807.15 and 420.65 is: 630.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.10 : 807.15 = 420.65 : x
  2. Step 2: Convert to fraction form
    538.10/807.15 = 420.65/x
  3. Step 3: Cross multiply
    538.10x = 807.15 × 420.65
  4. Step 4: Simplify right side
    538.10x = 339,527.65
  5. Step 5: Solve for x
    x = 339,527.65/538.10
  6. Step 6: Final answer
    x = 630.98

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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.