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Finding the Fourth Proportional to 665.91, 919.12 and 403.88

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Solution

The fourth proportional to 665.91, 919.12 and 403.88 is: 557.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.91 : 919.12 = 403.88 : x
  2. Step 2: Convert to fraction form
    665.91/919.12 = 403.88/x
  3. Step 3: Cross multiply
    665.91x = 919.12 × 403.88
  4. Step 4: Simplify right side
    665.91x = 371,208.58
  5. Step 5: Solve for x
    x = 371,208.58/665.91
  6. Step 6: Final answer
    x = 557.45

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.