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Finding the Fourth Proportional to 538.40, 807.65 and 213.69

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Solution

The fourth proportional to 538.40, 807.65 and 213.69 is: 320.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.40 : 807.65 = 213.69 : x
  2. Step 2: Convert to fraction form
    538.40/807.65 = 213.69/x
  3. Step 3: Cross multiply
    538.40x = 807.65 × 213.69
  4. Step 4: Simplify right side
    538.40x = 172,585.66
  5. Step 5: Solve for x
    x = 172,585.66/538.40
  6. Step 6: Final answer
    x = 320.56

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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.