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Finding the Fourth Proportional to 768.89, 1,061.07 and 419.60

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Solution

The fourth proportional to 768.89, 1,061.07 and 419.60 is: 579.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    768.89 : 1,061.07 = 419.60 : x
  2. Step 2: Convert to fraction form
    768.89/1,061.07 = 419.60/x
  3. Step 3: Cross multiply
    768.89x = 1,061.07 × 419.60
  4. Step 4: Simplify right side
    768.89x = 445,224.97
  5. Step 5: Solve for x
    x = 445,224.97/768.89
  6. Step 6: Final answer
    x = 579.05

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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.