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Finding the Fourth Proportional to 689.72, 1,034.83 and 279.15

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Solution

The fourth proportional to 689.72, 1,034.83 and 279.15 is: 418.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.72 : 1,034.83 = 279.15 : x
  2. Step 2: Convert to fraction form
    689.72/1,034.83 = 279.15/x
  3. Step 3: Cross multiply
    689.72x = 1,034.83 × 279.15
  4. Step 4: Simplify right side
    689.72x = 288,867.69
  5. Step 5: Solve for x
    x = 288,867.69/689.72
  6. Step 6: Final answer
    x = 418.82

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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.