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Finding the Fourth Proportional to 781.62, 1,080.57 and 748.80

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Solution

The fourth proportional to 781.62, 1,080.57 and 748.80 is: 1,035.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.62 : 1,080.57 = 748.80 : x
  2. Step 2: Convert to fraction form
    781.62/1,080.57 = 748.80/x
  3. Step 3: Cross multiply
    781.62x = 1,080.57 × 748.80
  4. Step 4: Simplify right side
    781.62x = 809,130.82
  5. Step 5: Solve for x
    x = 809,130.82/781.62
  6. Step 6: Final answer
    x = 1,035.20

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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.