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Finding the Fourth Proportional to 3,115, 4,672.50 and 806.50

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Solution

The fourth proportional to 3,115, 4,672.50 and 806.50 is: 1,209.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,115 : 4,672.50 = 806.50 : x
  2. Step 2: Convert to fraction form
    3,115/4,672.50 = 806.50/x
  3. Step 3: Cross multiply
    3,115x = 4,672.50 × 806.50
  4. Step 4: Simplify right side
    3,115x = 3,768,371.25
  5. Step 5: Solve for x
    x = 3,768,371.25/3,115
  6. Step 6: Final answer
    x = 1,209.75

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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.