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Finding the Fourth Proportional to 387.92, 535.31 and 210.87

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Solution

The fourth proportional to 387.92, 535.31 and 210.87 is: 290.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.92 : 535.31 = 210.87 : x
  2. Step 2: Convert to fraction form
    387.92/535.31 = 210.87/x
  3. Step 3: Cross multiply
    387.92x = 535.31 × 210.87
  4. Step 4: Simplify right side
    387.92x = 112,880.82
  5. Step 5: Solve for x
    x = 112,880.82/387.92
  6. Step 6: Final answer
    x = 290.99

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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.