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Finding the Fourth Proportional to 876.88, 1,209.12 and 628

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Solution

The fourth proportional to 876.88, 1,209.12 and 628 is: 865.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    876.88 : 1,209.12 = 628 : x
  2. Step 2: Convert to fraction form
    876.88/1,209.12 = 628/x
  3. Step 3: Cross multiply
    876.88x = 1,209.12 × 628
  4. Step 4: Simplify right side
    876.88x = 759,327.36
  5. Step 5: Solve for x
    x = 759,327.36/876.88
  6. Step 6: Final answer
    x = 865.94

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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.