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Finding the Fourth Proportional to 666.60, 919.86 and 371.85

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Solution

The fourth proportional to 666.60, 919.86 and 371.85 is: 513.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.60 : 919.86 = 371.85 : x
  2. Step 2: Convert to fraction form
    666.60/919.86 = 371.85/x
  3. Step 3: Cross multiply
    666.60x = 919.86 × 371.85
  4. Step 4: Simplify right side
    666.60x = 342,049.94
  5. Step 5: Solve for x
    x = 342,049.94/666.60
  6. Step 6: Final answer
    x = 513.13

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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.