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Finding the Fourth Proportional to 60.80, 83.40 and 55.20

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Solution

The fourth proportional to 60.80, 83.40 and 55.20 is: 75.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    60.80 : 83.40 = 55.20 : x
  2. Step 2: Convert to fraction form
    60.80/83.40 = 55.20/x
  3. Step 3: Cross multiply
    60.80x = 83.40 × 55.20
  4. Step 4: Simplify right side
    60.80x = 4,603.68
  5. Step 5: Solve for x
    x = 4,603.68/60.80
  6. Step 6: Final answer
    x = 75.72

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.