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Finding the Fourth Proportional to 521.80, 782.67 and 213.57

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Solution

The fourth proportional to 521.80, 782.67 and 213.57 is: 320.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.80 : 782.67 = 213.57 : x
  2. Step 2: Convert to fraction form
    521.80/782.67 = 213.57/x
  3. Step 3: Cross multiply
    521.80x = 782.67 × 213.57
  4. Step 4: Simplify right side
    521.80x = 167,154.83
  5. Step 5: Solve for x
    x = 167,154.83/521.80
  6. Step 6: Final answer
    x = 320.34

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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.