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Finding the Fourth Proportional to 780.76, 1,077.55 and 449.18

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Solution

The fourth proportional to 780.76, 1,077.55 and 449.18 is: 619.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.76 : 1,077.55 = 449.18 : x
  2. Step 2: Convert to fraction form
    780.76/1,077.55 = 449.18/x
  3. Step 3: Cross multiply
    780.76x = 1,077.55 × 449.18
  4. Step 4: Simplify right side
    780.76x = 484,008.52
  5. Step 5: Solve for x
    x = 484,008.52/780.76
  6. Step 6: Final answer
    x = 619.92

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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.