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Finding the Fourth Proportional to 771.06, 1,156.52 and 419.78

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Solution

The fourth proportional to 771.06, 1,156.52 and 419.78 is: 629.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    771.06 : 1,156.52 = 419.78 : x
  2. Step 2: Convert to fraction form
    771.06/1,156.52 = 419.78/x
  3. Step 3: Cross multiply
    771.06x = 1,156.52 × 419.78
  4. Step 4: Simplify right side
    771.06x = 485,487.91
  5. Step 5: Solve for x
    x = 485,487.91/771.06
  6. Step 6: Final answer
    x = 629.63

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.