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Finding the Fourth Proportional to 630.79, 870.55 and 351.11

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Solution

The fourth proportional to 630.79, 870.55 and 351.11 is: 484.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.79 : 870.55 = 351.11 : x
  2. Step 2: Convert to fraction form
    630.79/870.55 = 351.11/x
  3. Step 3: Cross multiply
    630.79x = 870.55 × 351.11
  4. Step 4: Simplify right side
    630.79x = 305,660.11
  5. Step 5: Solve for x
    x = 305,660.11/630.79
  6. Step 6: Final answer
    x = 484.57

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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.