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Finding the Fourth Proportional to 621.81, 858.30 and 401.35

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Solution

The fourth proportional to 621.81, 858.30 and 401.35 is: 553.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.81 : 858.30 = 401.35 : x
  2. Step 2: Convert to fraction form
    621.81/858.30 = 401.35/x
  3. Step 3: Cross multiply
    621.81x = 858.30 × 401.35
  4. Step 4: Simplify right side
    621.81x = 344,478.71
  5. Step 5: Solve for x
    x = 344,478.71/621.81
  6. Step 6: Final answer
    x = 553.99

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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.