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Finding the Fourth Proportional to 520.41, 780.69 and 191.30

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Solution

The fourth proportional to 520.41, 780.69 and 191.30 is: 286.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.41 : 780.69 = 191.30 : x
  2. Step 2: Convert to fraction form
    520.41/780.69 = 191.30/x
  3. Step 3: Cross multiply
    520.41x = 780.69 × 191.30
  4. Step 4: Simplify right side
    520.41x = 149,347.95
  5. Step 5: Solve for x
    x = 149,347.95/520.41
  6. Step 6: Final answer
    x = 286.98

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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.