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Finding the Fourth Proportional to 665.98, 999.29 and 255.40

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Solution

The fourth proportional to 665.98, 999.29 and 255.40 is: 383.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.98 : 999.29 = 255.40 : x
  2. Step 2: Convert to fraction form
    665.98/999.29 = 255.40/x
  3. Step 3: Cross multiply
    665.98x = 999.29 × 255.40
  4. Step 4: Simplify right side
    665.98x = 255,216.81
  5. Step 5: Solve for x
    x = 255,216.81/665.98
  6. Step 6: Final answer
    x = 383.22

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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.