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Finding the Fourth Proportional to 680.79, 939.15 and 418.35

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Solution

The fourth proportional to 680.79, 939.15 and 418.35 is: 577.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.79 : 939.15 = 418.35 : x
  2. Step 2: Convert to fraction form
    680.79/939.15 = 418.35/x
  3. Step 3: Cross multiply
    680.79x = 939.15 × 418.35
  4. Step 4: Simplify right side
    680.79x = 392,891.45
  5. Step 5: Solve for x
    x = 392,891.45/680.79
  6. Step 6: Final answer
    x = 577.11

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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.