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Finding the Fourth Proportional to 390.16, 538.37 and 250.31

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Solution

The fourth proportional to 390.16, 538.37 and 250.31 is: 345.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.16 : 538.37 = 250.31 : x
  2. Step 2: Convert to fraction form
    390.16/538.37 = 250.31/x
  3. Step 3: Cross multiply
    390.16x = 538.37 × 250.31
  4. Step 4: Simplify right side
    390.16x = 134,755.45
  5. Step 5: Solve for x
    x = 134,755.45/390.16
  6. Step 6: Final answer
    x = 345.39

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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.