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Finding the Fourth Proportional to 689.17, 950.82 and 390.37

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Solution

The fourth proportional to 689.17, 950.82 and 390.37 is: 538.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.17 : 950.82 = 390.37 : x
  2. Step 2: Convert to fraction form
    689.17/950.82 = 390.37/x
  3. Step 3: Cross multiply
    689.17x = 950.82 × 390.37
  4. Step 4: Simplify right side
    689.17x = 371,171.60
  5. Step 5: Solve for x
    x = 371,171.60/689.17
  6. Step 6: Final answer
    x = 538.58

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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.