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Finding the Fourth Proportional to 520.71, 780.13 and 442.95

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Solution

The fourth proportional to 520.71, 780.13 and 442.95 is: 663.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.71 : 780.13 = 442.95 : x
  2. Step 2: Convert to fraction form
    520.71/780.13 = 442.95/x
  3. Step 3: Cross multiply
    520.71x = 780.13 × 442.95
  4. Step 4: Simplify right side
    520.71x = 345,558.58
  5. Step 5: Solve for x
    x = 345,558.58/520.71
  6. Step 6: Final answer
    x = 663.63

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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.