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Finding the Fourth Proportional to 85.02, 117.27 and 78.18

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Solution

The fourth proportional to 85.02, 117.27 and 78.18 is: 107.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.02 : 117.27 = 78.18 : x
  2. Step 2: Convert to fraction form
    85.02/117.27 = 78.18/x
  3. Step 3: Cross multiply
    85.02x = 117.27 × 78.18
  4. Step 4: Simplify right side
    85.02x = 9,168.17
  5. Step 5: Solve for x
    x = 9,168.17/85.02
  6. Step 6: Final answer
    x = 107.84

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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.