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Finding the Fourth Proportional to 681.20, 939.77 and 419.06

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Solution

The fourth proportional to 681.20, 939.77 and 419.06 is: 578.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.20 : 939.77 = 419.06 : x
  2. Step 2: Convert to fraction form
    681.20/939.77 = 419.06/x
  3. Step 3: Cross multiply
    681.20x = 939.77 × 419.06
  4. Step 4: Simplify right side
    681.20x = 393,821.84
  5. Step 5: Solve for x
    x = 393,821.84/681.20
  6. Step 6: Final answer
    x = 578.13

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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.