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Finding the Fourth Proportional to 666.61, 998.42 and 434.79

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Solution

The fourth proportional to 666.61, 998.42 and 434.79 is: 651.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.61 : 998.42 = 434.79 : x
  2. Step 2: Convert to fraction form
    666.61/998.42 = 434.79/x
  3. Step 3: Cross multiply
    666.61x = 998.42 × 434.79
  4. Step 4: Simplify right side
    666.61x = 434,103.03
  5. Step 5: Solve for x
    x = 434,103.03/666.61
  6. Step 6: Final answer
    x = 651.21

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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.