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Finding the Fourth Proportional to 630.70, 870.42 and 368.71

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Solution

The fourth proportional to 630.70, 870.42 and 368.71 is: 508.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.70 : 870.42 = 368.71 : x
  2. Step 2: Convert to fraction form
    630.70/870.42 = 368.71/x
  3. Step 3: Cross multiply
    630.70x = 870.42 × 368.71
  4. Step 4: Simplify right side
    630.70x = 320,932.56
  5. Step 5: Solve for x
    x = 320,932.56/630.70
  6. Step 6: Final answer
    x = 508.85

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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.