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Finding the Fourth Proportional to 782.92, 1,080.39 and 428.85

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Solution

The fourth proportional to 782.92, 1,080.39 and 428.85 is: 591.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    782.92 : 1,080.39 = 428.85 : x
  2. Step 2: Convert to fraction form
    782.92/1,080.39 = 428.85/x
  3. Step 3: Cross multiply
    782.92x = 1,080.39 × 428.85
  4. Step 4: Simplify right side
    782.92x = 463,319.85
  5. Step 5: Solve for x
    x = 463,319.85/782.92
  6. Step 6: Final answer
    x = 591.78

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1.5x scale

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.