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Finding the Fourth Proportional to 781.57, 1,078.68 and 757.36

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Solution

The fourth proportional to 781.57, 1,078.68 and 757.36 is: 1,045.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.57 : 1,078.68 = 757.36 : x
  2. Step 2: Convert to fraction form
    781.57/1,078.68 = 757.36/x
  3. Step 3: Cross multiply
    781.57x = 1,078.68 × 757.36
  4. Step 4: Simplify right side
    781.57x = 816,949.08
  5. Step 5: Solve for x
    x = 816,949.08/781.57
  6. Step 6: Final answer
    x = 1,045.27

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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.