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Finding the Fourth Proportional to 415.29, 569.69 and 390.45

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Solution

The fourth proportional to 415.29, 569.69 and 390.45 is: 535.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.29 : 569.69 = 390.45 : x
  2. Step 2: Convert to fraction form
    415.29/569.69 = 390.45/x
  3. Step 3: Cross multiply
    415.29x = 569.69 × 390.45
  4. Step 4: Simplify right side
    415.29x = 222,435.46
  5. Step 5: Solve for x
    x = 222,435.46/415.29
  6. Step 6: Final answer
    x = 535.61

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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.