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Finding the Fourth Proportional to 676.80, 938.24 and 641.68

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Solution

The fourth proportional to 676.80, 938.24 and 641.68 is: 889.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    676.80 : 938.24 = 641.68 : x
  2. Step 2: Convert to fraction form
    676.80/938.24 = 641.68/x
  3. Step 3: Cross multiply
    676.80x = 938.24 × 641.68
  4. Step 4: Simplify right side
    676.80x = 602,049.84
  5. Step 5: Solve for x
    x = 602,049.84/676.80
  6. Step 6: Final answer
    x = 889.55

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.