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Finding the Fourth Proportional to 390.56, 584.44 and 287.56

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Solution

The fourth proportional to 390.56, 584.44 and 287.56 is: 430.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.56 : 584.44 = 287.56 : x
  2. Step 2: Convert to fraction form
    390.56/584.44 = 287.56/x
  3. Step 3: Cross multiply
    390.56x = 584.44 × 287.56
  4. Step 4: Simplify right side
    390.56x = 168,061.57
  5. Step 5: Solve for x
    x = 168,061.57/390.56
  6. Step 6: Final answer
    x = 430.31

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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.