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Finding the Fourth Proportional to 390.66, 540.28 and 349.14

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Solution

The fourth proportional to 390.66, 540.28 and 349.14 is: 482.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.66 : 540.28 = 349.14 : x
  2. Step 2: Convert to fraction form
    390.66/540.28 = 349.14/x
  3. Step 3: Cross multiply
    390.66x = 540.28 × 349.14
  4. Step 4: Simplify right side
    390.66x = 188,633.36
  5. Step 5: Solve for x
    x = 188,633.36/390.66
  6. Step 6: Final answer
    x = 482.86

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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.