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Finding the Fourth Proportional to 643.55, 888.08 and 348.81

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Solution

The fourth proportional to 643.55, 888.08 and 348.81 is: 481.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.55 : 888.08 = 348.81 : x
  2. Step 2: Convert to fraction form
    643.55/888.08 = 348.81/x
  3. Step 3: Cross multiply
    643.55x = 888.08 × 348.81
  4. Step 4: Simplify right side
    643.55x = 309,766.11
  5. Step 5: Solve for x
    x = 309,766.11/643.55
  6. Step 6: Final answer
    x = 481.34

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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.