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Finding the Fourth Proportional to 454.86, 628.29 and 399.78

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Solution

The fourth proportional to 454.86, 628.29 and 399.78 is: 552.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    454.86 : 628.29 = 399.78 : x
  2. Step 2: Convert to fraction form
    454.86/628.29 = 399.78/x
  3. Step 3: Cross multiply
    454.86x = 628.29 × 399.78
  4. Step 4: Simplify right side
    454.86x = 251,177.78
  5. Step 5: Solve for x
    x = 251,177.78/454.86
  6. Step 6: Final answer
    x = 552.21

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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.