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Finding the Fourth Proportional to 509.15, 706.22 and 490.70

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Solution

The fourth proportional to 509.15, 706.22 and 490.70 is: 680.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.15 : 706.22 = 490.70 : x
  2. Step 2: Convert to fraction form
    509.15/706.22 = 490.70/x
  3. Step 3: Cross multiply
    509.15x = 706.22 × 490.70
  4. Step 4: Simplify right side
    509.15x = 346,542.15
  5. Step 5: Solve for x
    x = 346,542.15/509.15
  6. Step 6: Final answer
    x = 680.64

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.