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Finding the Fourth Proportional to 439.19, 655.38 and 380.87

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Solution

The fourth proportional to 439.19, 655.38 and 380.87 is: 568.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.19 : 655.38 = 380.87 : x
  2. Step 2: Convert to fraction form
    439.19/655.38 = 380.87/x
  3. Step 3: Cross multiply
    439.19x = 655.38 × 380.87
  4. Step 4: Simplify right side
    439.19x = 249,612.68
  5. Step 5: Solve for x
    x = 249,612.68/439.19
  6. Step 6: Final answer
    x = 568.35

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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.