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Finding the Fourth Proportional to 642.90, 887.21 and 348.17

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Solution

The fourth proportional to 642.90, 887.21 and 348.17 is: 480.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.90 : 887.21 = 348.17 : x
  2. Step 2: Convert to fraction form
    642.90/887.21 = 348.17/x
  3. Step 3: Cross multiply
    642.90x = 887.21 × 348.17
  4. Step 4: Simplify right side
    642.90x = 308,895.03
  5. Step 5: Solve for x
    x = 308,895.03/642.90
  6. Step 6: Final answer
    x = 480.47

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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.