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Finding the Fourth Proportional to 538.71, 808.07 and 431.18

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Solution

The fourth proportional to 538.71, 808.07 and 431.18 is: 646.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.71 : 808.07 = 431.18 : x
  2. Step 2: Convert to fraction form
    538.71/808.07 = 431.18/x
  3. Step 3: Cross multiply
    538.71x = 808.07 × 431.18
  4. Step 4: Simplify right side
    538.71x = 348,425.64
  5. Step 5: Solve for x
    x = 348,425.64/538.71
  6. Step 6: Final answer
    x = 646.78

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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.