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Finding the Fourth Proportional to 77.78, 107.38 and 62.30

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Solution

The fourth proportional to 77.78, 107.38 and 62.30 is: 86.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.78 : 107.38 = 62.30 : x
  2. Step 2: Convert to fraction form
    77.78/107.38 = 62.30/x
  3. Step 3: Cross multiply
    77.78x = 107.38 × 62.30
  4. Step 4: Simplify right side
    77.78x = 6,689.77
  5. Step 5: Solve for x
    x = 6,689.77/77.78
  6. Step 6: Final answer
    x = 86.01

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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.