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Finding the Fourth Proportional to 328.35, 491.21 and 285.47

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Solution

The fourth proportional to 328.35, 491.21 and 285.47 is: 427.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.35 : 491.21 = 285.47 : x
  2. Step 2: Convert to fraction form
    328.35/491.21 = 285.47/x
  3. Step 3: Cross multiply
    328.35x = 491.21 × 285.47
  4. Step 4: Simplify right side
    328.35x = 140,229.12
  5. Step 5: Solve for x
    x = 140,229.12/328.35
  6. Step 6: Final answer
    x = 427.07

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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.