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Finding the Fourth Proportional to 538.90, 808.14 and 209.90

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Solution

The fourth proportional to 538.90, 808.14 and 209.90 is: 314.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.90 : 808.14 = 209.90 : x
  2. Step 2: Convert to fraction form
    538.90/808.14 = 209.90/x
  3. Step 3: Cross multiply
    538.90x = 808.14 × 209.90
  4. Step 4: Simplify right side
    538.90x = 169,628.59
  5. Step 5: Solve for x
    x = 169,628.59/538.90
  6. Step 6: Final answer
    x = 314.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.