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Finding the Fourth Proportional to 630.79, 870.91 and 382.55

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Solution

The fourth proportional to 630.79, 870.91 and 382.55 is: 528.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.79 : 870.91 = 382.55 : x
  2. Step 2: Convert to fraction form
    630.79/870.91 = 382.55/x
  3. Step 3: Cross multiply
    630.79x = 870.91 × 382.55
  4. Step 4: Simplify right side
    630.79x = 333,161.31
  5. Step 5: Solve for x
    x = 333,161.31/630.79
  6. Step 6: Final answer
    x = 528.17

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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.