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Finding the Fourth Proportional to 290.92, 438.47 and 278.56

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Solution

The fourth proportional to 290.92, 438.47 and 278.56 is: 419.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.92 : 438.47 = 278.56 : x
  2. Step 2: Convert to fraction form
    290.92/438.47 = 278.56/x
  3. Step 3: Cross multiply
    290.92x = 438.47 × 278.56
  4. Step 4: Simplify right side
    290.92x = 122,140.25
  5. Step 5: Solve for x
    x = 122,140.25/290.92
  6. Step 6: Final answer
    x = 419.85

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.