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Finding the Fourth Proportional to 520.63, 780.94 and 212.65

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Solution

The fourth proportional to 520.63, 780.94 and 212.65 is: 318.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.63 : 780.94 = 212.65 : x
  2. Step 2: Convert to fraction form
    520.63/780.94 = 212.65/x
  3. Step 3: Cross multiply
    520.63x = 780.94 × 212.65
  4. Step 4: Simplify right side
    520.63x = 166,062.45
  5. Step 5: Solve for x
    x = 166,062.45/520.63
  6. Step 6: Final answer
    x = 318.97

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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.