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Finding the Fourth Proportional to 478.96, 661.28 and 299.78

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Solution

The fourth proportional to 478.96, 661.28 and 299.78 is: 413.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.96 : 661.28 = 299.78 : x
  2. Step 2: Convert to fraction form
    478.96/661.28 = 299.78/x
  3. Step 3: Cross multiply
    478.96x = 661.28 × 299.78
  4. Step 4: Simplify right side
    478.96x = 198,238.52
  5. Step 5: Solve for x
    x = 198,238.52/478.96
  6. Step 6: Final answer
    x = 413.89

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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.