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Finding the Fourth Proportional to 643.09, 887.45 and 348.35

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Solution

The fourth proportional to 643.09, 887.45 and 348.35 is: 480.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.09 : 887.45 = 348.35 : x
  2. Step 2: Convert to fraction form
    643.09/887.45 = 348.35/x
  3. Step 3: Cross multiply
    643.09x = 887.45 × 348.35
  4. Step 4: Simplify right side
    643.09x = 309,143.21
  5. Step 5: Solve for x
    x = 309,143.21/643.09
  6. Step 6: Final answer
    x = 480.72

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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.