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Finding the Fourth Proportional to 642.03, 886.09 and 420.59

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Solution

The fourth proportional to 642.03, 886.09 and 420.59 is: 580.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.03 : 886.09 = 420.59 : x
  2. Step 2: Convert to fraction form
    642.03/886.09 = 420.59/x
  3. Step 3: Cross multiply
    642.03x = 886.09 × 420.59
  4. Step 4: Simplify right side
    642.03x = 372,680.59
  5. Step 5: Solve for x
    x = 372,680.59/642.03
  6. Step 6: Final answer
    x = 580.47

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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.