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Finding the Fourth Proportional to 641.62, 962.22 and 256.78

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Solution

The fourth proportional to 641.62, 962.22 and 256.78 is: 385.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.62 : 962.22 = 256.78 : x
  2. Step 2: Convert to fraction form
    641.62/962.22 = 256.78/x
  3. Step 3: Cross multiply
    641.62x = 962.22 × 256.78
  4. Step 4: Simplify right side
    641.62x = 247,078.85
  5. Step 5: Solve for x
    x = 247,078.85/641.62
  6. Step 6: Final answer
    x = 385.09

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1.5x scale

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.