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Finding the Fourth Proportional to 642.54, 881.55 and 611.58

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Solution

The fourth proportional to 642.54, 881.55 and 611.58 is: 839.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.54 : 881.55 = 611.58 : x
  2. Step 2: Convert to fraction form
    642.54/881.55 = 611.58/x
  3. Step 3: Cross multiply
    642.54x = 881.55 × 611.58
  4. Step 4: Simplify right side
    642.54x = 539,138.35
  5. Step 5: Solve for x
    x = 539,138.35/642.54
  6. Step 6: Final answer
    x = 839.07

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.