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Finding the Fourth Proportional to 78.49, 117.65 and 68.34

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Solution

The fourth proportional to 78.49, 117.65 and 68.34 is: 102.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.49 : 117.65 = 68.34 : x
  2. Step 2: Convert to fraction form
    78.49/117.65 = 68.34/x
  3. Step 3: Cross multiply
    78.49x = 117.65 × 68.34
  4. Step 4: Simplify right side
    78.49x = 8,039.77
  5. Step 5: Solve for x
    x = 8,039.77/78.49
  6. Step 6: Final answer
    x = 102.44

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.