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Finding the Fourth Proportional to 390.16, 538.39 and 232.78

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Solution

The fourth proportional to 390.16, 538.39 and 232.78 is: 321.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.16 : 538.39 = 232.78 : x
  2. Step 2: Convert to fraction form
    390.16/538.39 = 232.78/x
  3. Step 3: Cross multiply
    390.16x = 538.39 × 232.78
  4. Step 4: Simplify right side
    390.16x = 125,326.42
  5. Step 5: Solve for x
    x = 125,326.42/390.16
  6. Step 6: Final answer
    x = 321.22

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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.