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Finding the Fourth Proportional to 729, 1,006.20 and 630.72

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Solution

The fourth proportional to 729, 1,006.20 and 630.72 is: 870.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    729 : 1,006.20 = 630.72 : x
  2. Step 2: Convert to fraction form
    729/1,006.20 = 630.72/x
  3. Step 3: Cross multiply
    729x = 1,006.20 × 630.72
  4. Step 4: Simplify right side
    729x = 634,630.46
  5. Step 5: Solve for x
    x = 634,630.46/729
  6. Step 6: Final answer
    x = 870.55

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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.