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Finding the Fourth Proportional to 768.06, 1,151.06 and 420.87

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Solution

The fourth proportional to 768.06, 1,151.06 and 420.87 is: 630.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    768.06 : 1,151.06 = 420.87 : x
  2. Step 2: Convert to fraction form
    768.06/1,151.06 = 420.87/x
  3. Step 3: Cross multiply
    768.06x = 1,151.06 × 420.87
  4. Step 4: Simplify right side
    768.06x = 484,446.62
  5. Step 5: Solve for x
    x = 484,446.62/768.06
  6. Step 6: Final answer
    x = 630.74

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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.