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Finding the Fourth Proportional to 612.87, 919.55 and 247.70

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Solution

The fourth proportional to 612.87, 919.55 and 247.70 is: 371.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.87 : 919.55 = 247.70 : x
  2. Step 2: Convert to fraction form
    612.87/919.55 = 247.70/x
  3. Step 3: Cross multiply
    612.87x = 919.55 × 247.70
  4. Step 4: Simplify right side
    612.87x = 227,772.54
  5. Step 5: Solve for x
    x = 227,772.54/612.87
  6. Step 6: Final answer
    x = 371.65

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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.