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Finding the Fourth Proportional to 420.17, 578.75 and 353.70

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Solution

The fourth proportional to 420.17, 578.75 and 353.70 is: 487.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.17 : 578.75 = 353.70 : x
  2. Step 2: Convert to fraction form
    420.17/578.75 = 353.70/x
  3. Step 3: Cross multiply
    420.17x = 578.75 × 353.70
  4. Step 4: Simplify right side
    420.17x = 204,703.88
  5. Step 5: Solve for x
    x = 204,703.88/420.17
  6. Step 6: Final answer
    x = 487.19

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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.