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Finding the Fourth Proportional to 339.40, 506.78 and 278.65

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Solution

The fourth proportional to 339.40, 506.78 and 278.65 is: 416.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.40 : 506.78 = 278.65 : x
  2. Step 2: Convert to fraction form
    339.40/506.78 = 278.65/x
  3. Step 3: Cross multiply
    339.40x = 506.78 × 278.65
  4. Step 4: Simplify right side
    339.40x = 141,214.25
  5. Step 5: Solve for x
    x = 141,214.25/339.40
  6. Step 6: Final answer
    x = 416.07

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.