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Finding the Fourth Proportional to 780.98, 1,077.68 and 449.39

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Solution

The fourth proportional to 780.98, 1,077.68 and 449.39 is: 620.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.98 : 1,077.68 = 449.39 : x
  2. Step 2: Convert to fraction form
    780.98/1,077.68 = 449.39/x
  3. Step 3: Cross multiply
    780.98x = 1,077.68 × 449.39
  4. Step 4: Simplify right side
    780.98x = 484,298.62
  5. Step 5: Solve for x
    x = 484,298.62/780.98
  6. Step 6: Final answer
    x = 620.12

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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.