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Finding the Fourth Proportional to 415.10, 625.10 and 390.80

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Solution

The fourth proportional to 415.10, 625.10 and 390.80 is: 588.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.10 : 625.10 = 390.80 : x
  2. Step 2: Convert to fraction form
    415.10/625.10 = 390.80/x
  3. Step 3: Cross multiply
    415.10x = 625.10 × 390.80
  4. Step 4: Simplify right side
    415.10x = 244,289.08
  5. Step 5: Solve for x
    x = 244,289.08/415.10
  6. Step 6: Final answer
    x = 588.51

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.