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Finding the Fourth Proportional to 676.60, 1,007.79 and 645

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Solution

The fourth proportional to 676.60, 1,007.79 and 645 is: 960.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    676.60 : 1,007.79 = 645 : x
  2. Step 2: Convert to fraction form
    676.60/1,007.79 = 645/x
  3. Step 3: Cross multiply
    676.60x = 1,007.79 × 645
  4. Step 4: Simplify right side
    676.60x = 650,024.55
  5. Step 5: Solve for x
    x = 650,024.55/676.60
  6. Step 6: Final answer
    x = 960.72

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.