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Finding the Fourth Proportional to 630.87, 870.32 and 368.78

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Solution

The fourth proportional to 630.87, 870.32 and 368.78 is: 508.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.87 : 870.32 = 368.78 : x
  2. Step 2: Convert to fraction form
    630.87/870.32 = 368.78/x
  3. Step 3: Cross multiply
    630.87x = 870.32 × 368.78
  4. Step 4: Simplify right side
    630.87x = 320,950.41
  5. Step 5: Solve for x
    x = 320,950.41/630.87
  6. Step 6: Final answer
    x = 508.74

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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.