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Finding the Fourth Proportional to 389.49, 581.28 and 380.28

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Solution

The fourth proportional to 389.49, 581.28 and 380.28 is: 567.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.49 : 581.28 = 380.28 : x
  2. Step 2: Convert to fraction form
    389.49/581.28 = 380.28/x
  3. Step 3: Cross multiply
    389.49x = 581.28 × 380.28
  4. Step 4: Simplify right side
    389.49x = 221,049.16
  5. Step 5: Solve for x
    x = 221,049.16/389.49
  6. Step 6: Final answer
    x = 567.53

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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.