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Finding the Fourth Proportional to 390.68, 537.98 and 279.97

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Solution

The fourth proportional to 390.68, 537.98 and 279.97 is: 385.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.68 : 537.98 = 279.97 : x
  2. Step 2: Convert to fraction form
    390.68/537.98 = 279.97/x
  3. Step 3: Cross multiply
    390.68x = 537.98 × 279.97
  4. Step 4: Simplify right side
    390.68x = 150,614.87
  5. Step 5: Solve for x
    x = 150,614.87/390.68
  6. Step 6: Final answer
    x = 385.52

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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.