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Finding the Fourth Proportional to 520.44, 780.71 and 212.31

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Solution

The fourth proportional to 520.44, 780.71 and 212.31 is: 318.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.44 : 780.71 = 212.31 : x
  2. Step 2: Convert to fraction form
    520.44/780.71 = 212.31/x
  3. Step 3: Cross multiply
    520.44x = 780.71 × 212.31
  4. Step 4: Simplify right side
    520.44x = 165,751.48
  5. Step 5: Solve for x
    x = 165,751.48/520.44
  6. Step 6: Final answer
    x = 318.48

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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.