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Finding the Fourth Proportional to 642.81, 887.07 and 348.08

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Solution

The fourth proportional to 642.81, 887.07 and 348.08 is: 480.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.81 : 887.07 = 348.08 : x
  2. Step 2: Convert to fraction form
    642.81/887.07 = 348.08/x
  3. Step 3: Cross multiply
    642.81x = 887.07 × 348.08
  4. Step 4: Simplify right side
    642.81x = 308,768.20
  5. Step 5: Solve for x
    x = 308,768.20/642.81
  6. Step 6: Final answer
    x = 480.34

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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.