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Finding the Fourth Proportional to 666.31, 999.53 and 255.79

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Solution

The fourth proportional to 666.31, 999.53 and 255.79 is: 383.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.31 : 999.53 = 255.79 : x
  2. Step 2: Convert to fraction form
    666.31/999.53 = 255.79/x
  3. Step 3: Cross multiply
    666.31x = 999.53 × 255.79
  4. Step 4: Simplify right side
    666.31x = 255,668.50
  5. Step 5: Solve for x
    x = 255,668.50/666.31
  6. Step 6: Final answer
    x = 383.71

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1.5x scale

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.