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Finding the Fourth Proportional to 389.88, 538.07 and 307.62

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Solution

The fourth proportional to 389.88, 538.07 and 307.62 is: 424.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.88 : 538.07 = 307.62 : x
  2. Step 2: Convert to fraction form
    389.88/538.07 = 307.62/x
  3. Step 3: Cross multiply
    389.88x = 538.07 × 307.62
  4. Step 4: Simplify right side
    389.88x = 165,519.56
  5. Step 5: Solve for x
    x = 165,519.56/389.88
  6. Step 6: Final answer
    x = 424.54

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.