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Finding the Fourth Proportional to 641.51, 885.30 and 408.50

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Solution

The fourth proportional to 641.51, 885.30 and 408.50 is: 563.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.51 : 885.30 = 408.50 : x
  2. Step 2: Convert to fraction form
    641.51/885.30 = 408.50/x
  3. Step 3: Cross multiply
    641.51x = 885.30 × 408.50
  4. Step 4: Simplify right side
    641.51x = 361,645.05
  5. Step 5: Solve for x
    x = 361,645.05/641.51
  6. Step 6: Final answer
    x = 563.74

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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.