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Finding the Fourth Proportional to 621.63, 858.29 and 397.69

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Solution

The fourth proportional to 621.63, 858.29 and 397.69 is: 549.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.63 : 858.29 = 397.69 : x
  2. Step 2: Convert to fraction form
    621.63/858.29 = 397.69/x
  3. Step 3: Cross multiply
    621.63x = 858.29 × 397.69
  4. Step 4: Simplify right side
    621.63x = 341,329.22
  5. Step 5: Solve for x
    x = 341,329.22/621.63
  6. Step 6: Final answer
    x = 549.09

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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.