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Finding the Fourth Proportional to 71.60, 107.19 and 45.90

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Solution

The fourth proportional to 71.60, 107.19 and 45.90 is: 68.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.60 : 107.19 = 45.90 : x
  2. Step 2: Convert to fraction form
    71.60/107.19 = 45.90/x
  3. Step 3: Cross multiply
    71.60x = 107.19 × 45.90
  4. Step 4: Simplify right side
    71.60x = 4,920.02
  5. Step 5: Solve for x
    x = 4,920.02/71.60
  6. Step 6: Final answer
    x = 68.72

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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.