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Finding the Fourth Proportional to 641.84, 885.32 and 393.05

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Solution

The fourth proportional to 641.84, 885.32 and 393.05 is: 542.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.84 : 885.32 = 393.05 : x
  2. Step 2: Convert to fraction form
    641.84/885.32 = 393.05/x
  3. Step 3: Cross multiply
    641.84x = 885.32 × 393.05
  4. Step 4: Simplify right side
    641.84x = 347,973.06
  5. Step 5: Solve for x
    x = 347,973.06/641.84
  6. Step 6: Final answer
    x = 542.15

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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.