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Finding the Fourth Proportional to 390.97, 582.29 and 380.21

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Solution

The fourth proportional to 390.97, 582.29 and 380.21 is: 566.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.97 : 582.29 = 380.21 : x
  2. Step 2: Convert to fraction form
    390.97/582.29 = 380.21/x
  3. Step 3: Cross multiply
    390.97x = 582.29 × 380.21
  4. Step 4: Simplify right side
    390.97x = 221,390.52
  5. Step 5: Solve for x
    x = 221,390.52/390.97
  6. Step 6: Final answer
    x = 566.26

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.