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Finding the Fourth Proportional to 490.66, 677.99 and 386.55

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Solution

The fourth proportional to 490.66, 677.99 and 386.55 is: 534.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.66 : 677.99 = 386.55 : x
  2. Step 2: Convert to fraction form
    490.66/677.99 = 386.55/x
  3. Step 3: Cross multiply
    490.66x = 677.99 × 386.55
  4. Step 4: Simplify right side
    490.66x = 262,077.03
  5. Step 5: Solve for x
    x = 262,077.03/490.66
  6. Step 6: Final answer
    x = 534.13

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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.