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Finding the Fourth Proportional to 415.20, 621.57 and 307.47

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Solution

The fourth proportional to 415.20, 621.57 and 307.47 is: 460.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.20 : 621.57 = 307.47 : x
  2. Step 2: Convert to fraction form
    415.20/621.57 = 307.47/x
  3. Step 3: Cross multiply
    415.20x = 621.57 × 307.47
  4. Step 4: Simplify right side
    415.20x = 191,114.13
  5. Step 5: Solve for x
    x = 191,114.13/415.20
  6. Step 6: Final answer
    x = 460.29

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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.