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Finding the Fourth Proportional to 415.30, 618.64 and 405.70

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Solution

The fourth proportional to 415.30, 618.64 and 405.70 is: 604.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.30 : 618.64 = 405.70 : x
  2. Step 2: Convert to fraction form
    415.30/618.64 = 405.70/x
  3. Step 3: Cross multiply
    415.30x = 618.64 × 405.70
  4. Step 4: Simplify right side
    415.30x = 250,982.25
  5. Step 5: Solve for x
    x = 250,982.25/415.30
  6. Step 6: Final answer
    x = 604.34

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.