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Finding the Fourth Proportional to 666.28, 998.02 and 388.19

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Solution

The fourth proportional to 666.28, 998.02 and 388.19 is: 581.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.28 : 998.02 = 388.19 : x
  2. Step 2: Convert to fraction form
    666.28/998.02 = 388.19/x
  3. Step 3: Cross multiply
    666.28x = 998.02 × 388.19
  4. Step 4: Simplify right side
    666.28x = 387,424.36
  5. Step 5: Solve for x
    x = 387,424.36/666.28
  6. Step 6: Final answer
    x = 581.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.