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Finding the Fourth Proportional to 55.77, 76.86 and 50.78

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Solution

The fourth proportional to 55.77, 76.86 and 50.78 is: 69.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.77 : 76.86 = 50.78 : x
  2. Step 2: Convert to fraction form
    55.77/76.86 = 50.78/x
  3. Step 3: Cross multiply
    55.77x = 76.86 × 50.78
  4. Step 4: Simplify right side
    55.77x = 3,902.57
  5. Step 5: Solve for x
    x = 3,902.57/55.77
  6. Step 6: Final answer
    x = 69.98

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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.