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Finding the Fourth Proportional to 630.79, 870.57 and 382.11

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Solution

The fourth proportional to 630.79, 870.57 and 382.11 is: 527.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.79 : 870.57 = 382.11 : x
  2. Step 2: Convert to fraction form
    630.79/870.57 = 382.11/x
  3. Step 3: Cross multiply
    630.79x = 870.57 × 382.11
  4. Step 4: Simplify right side
    630.79x = 332,649.85
  5. Step 5: Solve for x
    x = 332,649.85/630.79
  6. Step 6: Final answer
    x = 527.36

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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.