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Finding the Fourth Proportional to 418.80, 575.52 and 399.78

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Solution

The fourth proportional to 418.80, 575.52 and 399.78 is: 549.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.80 : 575.52 = 399.78 : x
  2. Step 2: Convert to fraction form
    418.80/575.52 = 399.78/x
  3. Step 3: Cross multiply
    418.80x = 575.52 × 399.78
  4. Step 4: Simplify right side
    418.80x = 230,081.39
  5. Step 5: Solve for x
    x = 230,081.39/418.80
  6. Step 6: Final answer
    x = 549.38

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.