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Finding the Fourth Proportional to 666.81, 999.87 and 255.63

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Solution

The fourth proportional to 666.81, 999.87 and 255.63 is: 383.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.81 : 999.87 = 255.63 : x
  2. Step 2: Convert to fraction form
    666.81/999.87 = 255.63/x
  3. Step 3: Cross multiply
    666.81x = 999.87 × 255.63
  4. Step 4: Simplify right side
    666.81x = 255,596.77
  5. Step 5: Solve for x
    x = 255,596.77/666.81
  6. Step 6: Final answer
    x = 383.31

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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.