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Finding the Fourth Proportional to 55.28, 76.20 and 54.20

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Solution

The fourth proportional to 55.28, 76.20 and 54.20 is: 74.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.28 : 76.20 = 54.20 : x
  2. Step 2: Convert to fraction form
    55.28/76.20 = 54.20/x
  3. Step 3: Cross multiply
    55.28x = 76.20 × 54.20
  4. Step 4: Simplify right side
    55.28x = 4,130.04
  5. Step 5: Solve for x
    x = 4,130.04/55.28
  6. Step 6: Final answer
    x = 74.71

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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.