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Finding the Fourth Proportional to 630.73, 870.84 and 394.78

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Solution

The fourth proportional to 630.73, 870.84 and 394.78 is: 545.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.73 : 870.84 = 394.78 : x
  2. Step 2: Convert to fraction form
    630.73/870.84 = 394.78/x
  3. Step 3: Cross multiply
    630.73x = 870.84 × 394.78
  4. Step 4: Simplify right side
    630.73x = 343,790.22
  5. Step 5: Solve for x
    x = 343,790.22/630.73
  6. Step 6: Final answer
    x = 545.07

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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.