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Finding the Fourth Proportional to 782.87, 1,080.32 and 428.77

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Solution

The fourth proportional to 782.87, 1,080.32 and 428.77 is: 591.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.87 : 1,080.32 = 428.77 : x
  2. Step 2: Convert to fraction form
    782.87/1,080.32 = 428.77/x
  3. Step 3: Cross multiply
    782.87x = 1,080.32 × 428.77
  4. Step 4: Simplify right side
    782.87x = 463,209.62
  5. Step 5: Solve for x
    x = 463,209.62/782.87
  6. Step 6: Final answer
    x = 591.68

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.