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Finding the Fourth Proportional to 642.85, 887.13 and 348.12

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Solution

The fourth proportional to 642.85, 887.13 and 348.12 is: 480.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.85 : 887.13 = 348.12 : x
  2. Step 2: Convert to fraction form
    642.85/887.13 = 348.12/x
  3. Step 3: Cross multiply
    642.85x = 887.13 × 348.12
  4. Step 4: Simplify right side
    642.85x = 308,827.70
  5. Step 5: Solve for x
    x = 308,827.70/642.85
  6. Step 6: Final answer
    x = 480.40

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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.