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Finding the Fourth Proportional to 780.21, 1,077.03 and 517.77

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Solution

The fourth proportional to 780.21, 1,077.03 and 517.77 is: 714.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.21 : 1,077.03 = 517.77 : x
  2. Step 2: Convert to fraction form
    780.21/1,077.03 = 517.77/x
  3. Step 3: Cross multiply
    780.21x = 1,077.03 × 517.77
  4. Step 4: Simplify right side
    780.21x = 557,653.82
  5. Step 5: Solve for x
    x = 557,653.82/780.21
  6. Step 6: Final answer
    x = 714.75

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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.