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Finding the Fourth Proportional to 505.65, 698.13 and 319.20

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Solution

The fourth proportional to 505.65, 698.13 and 319.20 is: 440.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.65 : 698.13 = 319.20 : x
  2. Step 2: Convert to fraction form
    505.65/698.13 = 319.20/x
  3. Step 3: Cross multiply
    505.65x = 698.13 × 319.20
  4. Step 4: Simplify right side
    505.65x = 222,843.10
  5. Step 5: Solve for x
    x = 222,843.10/505.65
  6. Step 6: Final answer
    x = 440.71

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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.