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Finding the Fourth Proportional to 520.90, 777.11 and 478.57

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Solution

The fourth proportional to 520.90, 777.11 and 478.57 is: 713.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.90 : 777.11 = 478.57 : x
  2. Step 2: Convert to fraction form
    520.90/777.11 = 478.57/x
  3. Step 3: Cross multiply
    520.90x = 777.11 × 478.57
  4. Step 4: Simplify right side
    520.90x = 371,901.53
  5. Step 5: Solve for x
    x = 371,901.53/520.90
  6. Step 6: Final answer
    x = 713.96

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.