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Finding the Fourth Proportional to 518.34, 777.78 and 287.43

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Solution

The fourth proportional to 518.34, 777.78 and 287.43 is: 431.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.34 : 777.78 = 287.43 : x
  2. Step 2: Convert to fraction form
    518.34/777.78 = 287.43/x
  3. Step 3: Cross multiply
    518.34x = 777.78 × 287.43
  4. Step 4: Simplify right side
    518.34x = 223,557.31
  5. Step 5: Solve for x
    x = 223,557.31/518.34
  6. Step 6: Final answer
    x = 431.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.