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Finding the Fourth Proportional to 405.24, 608.85 and 390.66

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Solution

The fourth proportional to 405.24, 608.85 and 390.66 is: 586.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.24 : 608.85 = 390.66 : x
  2. Step 2: Convert to fraction form
    405.24/608.85 = 390.66/x
  3. Step 3: Cross multiply
    405.24x = 608.85 × 390.66
  4. Step 4: Simplify right side
    405.24x = 237,853.34
  5. Step 5: Solve for x
    x = 237,853.34/405.24
  6. Step 6: Final answer
    x = 586.94

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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.