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Finding the Fourth Proportional to 85.95, 118.64 and 77.75

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Solution

The fourth proportional to 85.95, 118.64 and 77.75 is: 107.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.95 : 118.64 = 77.75 : x
  2. Step 2: Convert to fraction form
    85.95/118.64 = 77.75/x
  3. Step 3: Cross multiply
    85.95x = 118.64 × 77.75
  4. Step 4: Simplify right side
    85.95x = 9,223.28
  5. Step 5: Solve for x
    x = 9,223.28/85.95
  6. Step 6: Final answer
    x = 107.31

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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.