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Finding the Fourth Proportional to 91.87, 137.57 and 51.30

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Solution

The fourth proportional to 91.87, 137.57 and 51.30 is: 76.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.87 : 137.57 = 51.30 : x
  2. Step 2: Convert to fraction form
    91.87/137.57 = 51.30/x
  3. Step 3: Cross multiply
    91.87x = 137.57 × 51.30
  4. Step 4: Simplify right side
    91.87x = 7,057.08
  5. Step 5: Solve for x
    x = 7,057.08/91.87
  6. Step 6: Final answer
    x = 76.82

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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.