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Finding the Fourth Proportional to 55.78, 83.72 and 28.75

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Solution

The fourth proportional to 55.78, 83.72 and 28.75 is: 43.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.78 : 83.72 = 28.75 : x
  2. Step 2: Convert to fraction form
    55.78/83.72 = 28.75/x
  3. Step 3: Cross multiply
    55.78x = 83.72 × 28.75
  4. Step 4: Simplify right side
    55.78x = 2,406.95
  5. Step 5: Solve for x
    x = 2,406.95/55.78
  6. Step 6: Final answer
    x = 43.15

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.