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Finding the Fourth Proportional to 390.83, 540.07 and 286.34

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Solution

The fourth proportional to 390.83, 540.07 and 286.34 is: 395.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.83 : 540.07 = 286.34 : x
  2. Step 2: Convert to fraction form
    390.83/540.07 = 286.34/x
  3. Step 3: Cross multiply
    390.83x = 540.07 × 286.34
  4. Step 4: Simplify right side
    390.83x = 154,640.23
  5. Step 5: Solve for x
    x = 154,640.23/390.83
  6. Step 6: Final answer
    x = 395.68

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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.