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Finding the Fourth Proportional to 520.30, 780 and 346.72

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Solution

The fourth proportional to 520.30, 780 and 346.72 is: 519.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.30 : 780 = 346.72 : x
  2. Step 2: Convert to fraction form
    520.30/780 = 346.72/x
  3. Step 3: Cross multiply
    520.30x = 780 × 346.72
  4. Step 4: Simplify right side
    520.30x = 270,441.60
  5. Step 5: Solve for x
    x = 270,441.60/520.30
  6. Step 6: Final answer
    x = 519.78

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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.