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Finding the Fourth Proportional to 520.76, 780.93 and 260.66

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Solution

The fourth proportional to 520.76, 780.93 and 260.66 is: 390.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.76 : 780.93 = 260.66 : x
  2. Step 2: Convert to fraction form
    520.76/780.93 = 260.66/x
  3. Step 3: Cross multiply
    520.76x = 780.93 × 260.66
  4. Step 4: Simplify right side
    520.76x = 203,559.17
  5. Step 5: Solve for x
    x = 203,559.17/520.76
  6. Step 6: Final answer
    x = 390.89

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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.