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Finding the Fourth Proportional to 77.14, 115.30 and 65.80

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Solution

The fourth proportional to 77.14, 115.30 and 65.80 is: 98.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.14 : 115.30 = 65.80 : x
  2. Step 2: Convert to fraction form
    77.14/115.30 = 65.80/x
  3. Step 3: Cross multiply
    77.14x = 115.30 × 65.80
  4. Step 4: Simplify right side
    77.14x = 7,586.74
  5. Step 5: Solve for x
    x = 7,586.74/77.14
  6. Step 6: Final answer
    x = 98.35

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.