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Finding the Fourth Proportional to 666.81, 920.20 and 379.35

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Solution

The fourth proportional to 666.81, 920.20 and 379.35 is: 523.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.81 : 920.20 = 379.35 : x
  2. Step 2: Convert to fraction form
    666.81/920.20 = 379.35/x
  3. Step 3: Cross multiply
    666.81x = 920.20 × 379.35
  4. Step 4: Simplify right side
    666.81x = 349,077.87
  5. Step 5: Solve for x
    x = 349,077.87/666.81
  6. Step 6: Final answer
    x = 523.50

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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.