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Finding the Fourth Proportional to 778.20, 1,074.27 and 498.54

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Solution

The fourth proportional to 778.20, 1,074.27 and 498.54 is: 688.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.20 : 1,074.27 = 498.54 : x
  2. Step 2: Convert to fraction form
    778.20/1,074.27 = 498.54/x
  3. Step 3: Cross multiply
    778.20x = 1,074.27 × 498.54
  4. Step 4: Simplify right side
    778.20x = 535,566.57
  5. Step 5: Solve for x
    x = 535,566.57/778.20
  6. Step 6: Final answer
    x = 688.21

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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.