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Finding the Fourth Proportional to 356.30, 490.71 and 330.78

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Solution

The fourth proportional to 356.30, 490.71 and 330.78 is: 455.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    356.30 : 490.71 = 330.78 : x
  2. Step 2: Convert to fraction form
    356.30/490.71 = 330.78/x
  3. Step 3: Cross multiply
    356.30x = 490.71 × 330.78
  4. Step 4: Simplify right side
    356.30x = 162,318.27
  5. Step 5: Solve for x
    x = 162,318.27/356.30
  6. Step 6: Final answer
    x = 455.57

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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.