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Finding the Fourth Proportional to 689.00, 950.84 and 390.31

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Solution

The fourth proportional to 689.00, 950.84 and 390.31 is: 538.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.00 : 950.84 = 390.31 : x
  2. Step 2: Convert to fraction form
    689.00/950.84 = 390.31/x
  3. Step 3: Cross multiply
    689.00x = 950.84 × 390.31
  4. Step 4: Simplify right side
    689.00x = 371,120.96
  5. Step 5: Solve for x
    x = 371,120.96/689.00
  6. Step 6: Final answer
    x = 538.64

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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.