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Finding the Fourth Proportional to 630.65, 869.96 and 428.69

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Solution

The fourth proportional to 630.65, 869.96 and 428.69 is: 591.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.65 : 869.96 = 428.69 : x
  2. Step 2: Convert to fraction form
    630.65/869.96 = 428.69/x
  3. Step 3: Cross multiply
    630.65x = 869.96 × 428.69
  4. Step 4: Simplify right side
    630.65x = 372,936.66
  5. Step 5: Solve for x
    x = 372,936.66/630.65
  6. Step 6: Final answer
    x = 591.36

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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.