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Finding the Fourth Proportional to 666.56, 919.79 and 371.78

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Solution

The fourth proportional to 666.56, 919.79 and 371.78 is: 513.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.56 : 919.79 = 371.78 : x
  2. Step 2: Convert to fraction form
    666.56/919.79 = 371.78/x
  3. Step 3: Cross multiply
    666.56x = 919.79 × 371.78
  4. Step 4: Simplify right side
    666.56x = 341,957.91
  5. Step 5: Solve for x
    x = 341,957.91/666.56
  6. Step 6: Final answer
    x = 513.02

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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.