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Finding the Fourth Proportional to 621.51, 930.33 and 389.61

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Solution

The fourth proportional to 621.51, 930.33 and 389.61 is: 583.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.51 : 930.33 = 389.61 : x
  2. Step 2: Convert to fraction form
    621.51/930.33 = 389.61/x
  3. Step 3: Cross multiply
    621.51x = 930.33 × 389.61
  4. Step 4: Simplify right side
    621.51x = 362,465.87
  5. Step 5: Solve for x
    x = 362,465.87/621.51
  6. Step 6: Final answer
    x = 583.20

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.