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Finding the Fourth Proportional to 642.54, 886.94 and 406.89

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Solution

The fourth proportional to 642.54, 886.94 and 406.89 is: 561.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.54 : 886.94 = 406.89 : x
  2. Step 2: Convert to fraction form
    642.54/886.94 = 406.89/x
  3. Step 3: Cross multiply
    642.54x = 886.94 × 406.89
  4. Step 4: Simplify right side
    642.54x = 360,887.02
  5. Step 5: Solve for x
    x = 360,887.02/642.54
  6. Step 6: Final answer
    x = 561.66

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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.