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Finding the Fourth Proportional to 520.85, 780.76 and 260.46

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Solution

The fourth proportional to 520.85, 780.76 and 260.46 is: 390.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.85 : 780.76 = 260.46 : x
  2. Step 2: Convert to fraction form
    520.85/780.76 = 260.46/x
  3. Step 3: Cross multiply
    520.85x = 780.76 × 260.46
  4. Step 4: Simplify right side
    520.85x = 203,354.51
  5. Step 5: Solve for x
    x = 203,354.51/520.85
  6. Step 6: Final answer
    x = 390.43

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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.