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Finding the Fourth Proportional to 86.84, 119.90 and 55.77

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Solution

The fourth proportional to 86.84, 119.90 and 55.77 is: 77.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.84 : 119.90 = 55.77 : x
  2. Step 2: Convert to fraction form
    86.84/119.90 = 55.77/x
  3. Step 3: Cross multiply
    86.84x = 119.90 × 55.77
  4. Step 4: Simplify right side
    86.84x = 6,686.54
  5. Step 5: Solve for x
    x = 6,686.54/86.84
  6. Step 6: Final answer
    x = 77.00

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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.