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Finding the Fourth Proportional to 666.78, 920.16 and 372.05

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Solution

The fourth proportional to 666.78, 920.16 and 372.05 is: 513.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.78 : 920.16 = 372.05 : x
  2. Step 2: Convert to fraction form
    666.78/920.16 = 372.05/x
  3. Step 3: Cross multiply
    666.78x = 920.16 × 372.05
  4. Step 4: Simplify right side
    666.78x = 342,348.30
  5. Step 5: Solve for x
    x = 342,348.30/666.78
  6. Step 6: Final answer
    x = 513.43

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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.