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Finding the Fourth Proportional to 642.19, 885.34 and 406.02

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Solution

The fourth proportional to 642.19, 885.34 and 406.02 is: 559.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.19 : 885.34 = 406.02 : x
  2. Step 2: Convert to fraction form
    642.19/885.34 = 406.02/x
  3. Step 3: Cross multiply
    642.19x = 885.34 × 406.02
  4. Step 4: Simplify right side
    642.19x = 359,464.18
  5. Step 5: Solve for x
    x = 359,464.18/642.19
  6. Step 6: Final answer
    x = 559.75

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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.