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Finding the Fourth Proportional to 638.15, 880.20 and 555.12

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Solution

The fourth proportional to 638.15, 880.20 and 555.12 is: 765.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.15 : 880.20 = 555.12 : x
  2. Step 2: Convert to fraction form
    638.15/880.20 = 555.12/x
  3. Step 3: Cross multiply
    638.15x = 880.20 × 555.12
  4. Step 4: Simplify right side
    638.15x = 488,616.62
  5. Step 5: Solve for x
    x = 488,616.62/638.15
  6. Step 6: Final answer
    x = 765.68

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1.5x scale

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.