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Finding the Fourth Proportional to 78.32, 107.96 and 63.74

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Solution

The fourth proportional to 78.32, 107.96 and 63.74 is: 87.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.32 : 107.96 = 63.74 : x
  2. Step 2: Convert to fraction form
    78.32/107.96 = 63.74/x
  3. Step 3: Cross multiply
    78.32x = 107.96 × 63.74
  4. Step 4: Simplify right side
    78.32x = 6,881.37
  5. Step 5: Solve for x
    x = 6,881.37/78.32
  6. Step 6: Final answer
    x = 87.86

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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.