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Finding the Fourth Proportional to 630.39, 869.91 and 346.80

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Solution

The fourth proportional to 630.39, 869.91 and 346.80 is: 478.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.39 : 869.91 = 346.80 : x
  2. Step 2: Convert to fraction form
    630.39/869.91 = 346.80/x
  3. Step 3: Cross multiply
    630.39x = 869.91 × 346.80
  4. Step 4: Simplify right side
    630.39x = 301,684.79
  5. Step 5: Solve for x
    x = 301,684.79/630.39
  6. Step 6: Final answer
    x = 478.57

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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.