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Finding the Fourth Proportional to 385.58, 531.92 and 280.50

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Solution

The fourth proportional to 385.58, 531.92 and 280.50 is: 386.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.58 : 531.92 = 280.50 : x
  2. Step 2: Convert to fraction form
    385.58/531.92 = 280.50/x
  3. Step 3: Cross multiply
    385.58x = 531.92 × 280.50
  4. Step 4: Simplify right side
    385.58x = 149,199.50
  5. Step 5: Solve for x
    x = 149,199.50/385.58
  6. Step 6: Final answer
    x = 386.95

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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.