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Finding the Fourth Proportional to 505.86, 698.25 and 306.80

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Solution

The fourth proportional to 505.86, 698.25 and 306.80 is: 423.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.86 : 698.25 = 306.80 : x
  2. Step 2: Convert to fraction form
    505.86/698.25 = 306.80/x
  3. Step 3: Cross multiply
    505.86x = 698.25 × 306.80
  4. Step 4: Simplify right side
    505.86x = 214,223.38
  5. Step 5: Solve for x
    x = 214,223.38/505.86
  6. Step 6: Final answer
    x = 423.49

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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.