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Finding the Fourth Proportional to 505.49, 697.40 and 306.38

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Solution

The fourth proportional to 505.49, 697.40 and 306.38 is: 422.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.49 : 697.40 = 306.38 : x
  2. Step 2: Convert to fraction form
    505.49/697.40 = 306.38/x
  3. Step 3: Cross multiply
    505.49x = 697.40 × 306.38
  4. Step 4: Simplify right side
    505.49x = 213,667.88
  5. Step 5: Solve for x
    x = 213,667.88/505.49
  6. Step 6: Final answer
    x = 422.70

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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.