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Finding the Fourth Proportional to 390.56, 538.43 and 266.09

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Solution

The fourth proportional to 390.56, 538.43 and 266.09 is: 366.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.56 : 538.43 = 266.09 : x
  2. Step 2: Convert to fraction form
    390.56/538.43 = 266.09/x
  3. Step 3: Cross multiply
    390.56x = 538.43 × 266.09
  4. Step 4: Simplify right side
    390.56x = 143,266.82
  5. Step 5: Solve for x
    x = 143,266.82/390.56
  6. Step 6: Final answer
    x = 366.83

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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.