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Finding the Fourth Proportional to 389.55, 538.36 and 319.50

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Solution

The fourth proportional to 389.55, 538.36 and 319.50 is: 441.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.55 : 538.36 = 319.50 : x
  2. Step 2: Convert to fraction form
    389.55/538.36 = 319.50/x
  3. Step 3: Cross multiply
    389.55x = 538.36 × 319.50
  4. Step 4: Simplify right side
    389.55x = 172,006.02
  5. Step 5: Solve for x
    x = 172,006.02/389.55
  6. Step 6: Final answer
    x = 441.55

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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.