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Finding the Fourth Proportional to 781.07, 1,077.53 and 449.30

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Solution

The fourth proportional to 781.07, 1,077.53 and 449.30 is: 619.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    781.07 : 1,077.53 = 449.30 : x
  2. Step 2: Convert to fraction form
    781.07/1,077.53 = 449.30/x
  3. Step 3: Cross multiply
    781.07x = 1,077.53 × 449.30
  4. Step 4: Simplify right side
    781.07x = 484,134.68
  5. Step 5: Solve for x
    x = 484,134.68/781.07
  6. Step 6: Final answer
    x = 619.84

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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.