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Finding the Fourth Proportional to 338.58, 505.39 and 309.72

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Solution

The fourth proportional to 338.58, 505.39 and 309.72 is: 462.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.58 : 505.39 = 309.72 : x
  2. Step 2: Convert to fraction form
    338.58/505.39 = 309.72/x
  3. Step 3: Cross multiply
    338.58x = 505.39 × 309.72
  4. Step 4: Simplify right side
    338.58x = 156,531.09
  5. Step 5: Solve for x
    x = 156,531.09/338.58
  6. Step 6: Final answer
    x = 462.32

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.