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Finding the Fourth Proportional to 385.51, 531.52 and 280.52

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Solution

The fourth proportional to 385.51, 531.52 and 280.52 is: 386.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.51 : 531.52 = 280.52 : x
  2. Step 2: Convert to fraction form
    385.51/531.52 = 280.52/x
  3. Step 3: Cross multiply
    385.51x = 531.52 × 280.52
  4. Step 4: Simplify right side
    385.51x = 149,098.63
  5. Step 5: Solve for x
    x = 149,098.63/385.51
  6. Step 6: Final answer
    x = 386.76

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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.