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Finding the Fourth Proportional to 494.80, 680.27 and 420.70

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Solution

The fourth proportional to 494.80, 680.27 and 420.70 is: 578.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    494.80 : 680.27 = 420.70 : x
  2. Step 2: Convert to fraction form
    494.80/680.27 = 420.70/x
  3. Step 3: Cross multiply
    494.80x = 680.27 × 420.70
  4. Step 4: Simplify right side
    494.80x = 286,189.59
  5. Step 5: Solve for x
    x = 286,189.59/494.80
  6. Step 6: Final answer
    x = 578.39

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.