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Finding the Fourth Proportional to 390.93, 538.97 and 297.78

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Solution

The fourth proportional to 390.93, 538.97 and 297.78 is: 410.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.93 : 538.97 = 297.78 : x
  2. Step 2: Convert to fraction form
    390.93/538.97 = 297.78/x
  3. Step 3: Cross multiply
    390.93x = 538.97 × 297.78
  4. Step 4: Simplify right side
    390.93x = 160,493.00
  5. Step 5: Solve for x
    x = 160,493.00/390.93
  6. Step 6: Final answer
    x = 410.54

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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.