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Finding the Fourth Proportional to 55.38, 76.38 and 40.80

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Solution

The fourth proportional to 55.38, 76.38 and 40.80 is: 56.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.38 : 76.38 = 40.80 : x
  2. Step 2: Convert to fraction form
    55.38/76.38 = 40.80/x
  3. Step 3: Cross multiply
    55.38x = 76.38 × 40.80
  4. Step 4: Simplify right side
    55.38x = 3,116.30
  5. Step 5: Solve for x
    x = 3,116.30/55.38
  6. Step 6: Final answer
    x = 56.27

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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.