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Finding the Fourth Proportional to 390.79, 586.87 and 360.31

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Solution

The fourth proportional to 390.79, 586.87 and 360.31 is: 541.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.79 : 586.87 = 360.31 : x
  2. Step 2: Convert to fraction form
    390.79/586.87 = 360.31/x
  3. Step 3: Cross multiply
    390.79x = 586.87 × 360.31
  4. Step 4: Simplify right side
    390.79x = 211,453.33
  5. Step 5: Solve for x
    x = 211,453.33/390.79
  6. Step 6: Final answer
    x = 541.09

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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.