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Finding the Fourth Proportional to 78.87, 108.71 and 69.93

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Solution

The fourth proportional to 78.87, 108.71 and 69.93 is: 96.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.87 : 108.71 = 69.93 : x
  2. Step 2: Convert to fraction form
    78.87/108.71 = 69.93/x
  3. Step 3: Cross multiply
    78.87x = 108.71 × 69.93
  4. Step 4: Simplify right side
    78.87x = 7,601.74
  5. Step 5: Solve for x
    x = 7,601.74/78.87
  6. Step 6: Final answer
    x = 96.38

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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.