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Finding the Fourth Proportional to 666.79, 999.71 and 255.58

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Solution

The fourth proportional to 666.79, 999.71 and 255.58 is: 383.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.79 : 999.71 = 255.58 : x
  2. Step 2: Convert to fraction form
    666.79/999.71 = 255.58/x
  3. Step 3: Cross multiply
    666.79x = 999.71 × 255.58
  4. Step 4: Simplify right side
    666.79x = 255,502.10
  5. Step 5: Solve for x
    x = 255,502.10/666.79
  6. Step 6: Final answer
    x = 383.18

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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.