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Finding the Fourth Proportional to 642.05, 886.04 and 393.50

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Solution

The fourth proportional to 642.05, 886.04 and 393.50 is: 543.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.05 : 886.04 = 393.50 : x
  2. Step 2: Convert to fraction form
    642.05/886.04 = 393.50/x
  3. Step 3: Cross multiply
    642.05x = 886.04 × 393.50
  4. Step 4: Simplify right side
    642.05x = 348,650.34
  5. Step 5: Solve for x
    x = 348,650.34/642.05
  6. Step 6: Final answer
    x = 543.03

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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.