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Finding the Fourth Proportional to 78.58, 108.30 and 73.90

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Solution

The fourth proportional to 78.58, 108.30 and 73.90 is: 101.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.58 : 108.30 = 73.90 : x
  2. Step 2: Convert to fraction form
    78.58/108.30 = 73.90/x
  3. Step 3: Cross multiply
    78.58x = 108.30 × 73.90
  4. Step 4: Simplify right side
    78.58x = 8,003.37
  5. Step 5: Solve for x
    x = 8,003.37/78.58
  6. Step 6: Final answer
    x = 101.85

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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.