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Finding the Fourth Proportional to 517.66, 779.99 and 428.36

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Solution

The fourth proportional to 517.66, 779.99 and 428.36 is: 645.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    517.66 : 779.99 = 428.36 : x
  2. Step 2: Convert to fraction form
    517.66/779.99 = 428.36/x
  3. Step 3: Cross multiply
    517.66x = 779.99 × 428.36
  4. Step 4: Simplify right side
    517.66x = 334,113.69
  5. Step 5: Solve for x
    x = 334,113.69/517.66
  6. Step 6: Final answer
    x = 645.43

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.