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Finding the Fourth Proportional to 780.18, 1,076.82 and 469.68

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Solution

The fourth proportional to 780.18, 1,076.82 and 469.68 is: 648.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.18 : 1,076.82 = 469.68 : x
  2. Step 2: Convert to fraction form
    780.18/1,076.82 = 469.68/x
  3. Step 3: Cross multiply
    780.18x = 1,076.82 × 469.68
  4. Step 4: Simplify right side
    780.18x = 505,760.82
  5. Step 5: Solve for x
    x = 505,760.82/780.18
  6. Step 6: Final answer
    x = 648.26

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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.