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Finding the Fourth Proportional to 389.68, 537.92 and 279.20

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Solution

The fourth proportional to 389.68, 537.92 and 279.20 is: 385.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    389.68 : 537.92 = 279.20 : x
  2. Step 2: Convert to fraction form
    389.68/537.92 = 279.20/x
  3. Step 3: Cross multiply
    389.68x = 537.92 × 279.20
  4. Step 4: Simplify right side
    389.68x = 150,187.26
  5. Step 5: Solve for x
    x = 150,187.26/389.68
  6. Step 6: Final answer
    x = 385.41

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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.