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Finding the Fourth Proportional to 666.38, 999.71 and 281.63

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Solution

The fourth proportional to 666.38, 999.71 and 281.63 is: 422.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.38 : 999.71 = 281.63 : x
  2. Step 2: Convert to fraction form
    666.38/999.71 = 281.63/x
  3. Step 3: Cross multiply
    666.38x = 999.71 × 281.63
  4. Step 4: Simplify right side
    666.38x = 281,541.92
  5. Step 5: Solve for x
    x = 281,541.92/666.38
  6. Step 6: Final answer
    x = 422.50

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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.