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Finding the Fourth Proportional to 629.91, 869.40 and 409.05

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Solution

The fourth proportional to 629.91, 869.40 and 409.05 is: 564.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    629.91 : 869.40 = 409.05 : x
  2. Step 2: Convert to fraction form
    629.91/869.40 = 409.05/x
  3. Step 3: Cross multiply
    629.91x = 869.40 × 409.05
  4. Step 4: Simplify right side
    629.91x = 355,628.07
  5. Step 5: Solve for x
    x = 355,628.07/629.91
  6. Step 6: Final answer
    x = 564.57

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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.