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Finding the Fourth Proportional to 78.99, 118.07 and 77.37

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Solution

The fourth proportional to 78.99, 118.07 and 77.37 is: 115.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.99 : 118.07 = 77.37 : x
  2. Step 2: Convert to fraction form
    78.99/118.07 = 77.37/x
  3. Step 3: Cross multiply
    78.99x = 118.07 × 77.37
  4. Step 4: Simplify right side
    78.99x = 9,134.69
  5. Step 5: Solve for x
    x = 9,134.69/78.99
  6. Step 6: Final answer
    x = 115.64

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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.