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Finding the Fourth Proportional to 391.08, 590.40 and 388.92

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Solution

The fourth proportional to 391.08, 590.40 and 388.92 is: 587.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.08 : 590.40 = 388.92 : x
  2. Step 2: Convert to fraction form
    391.08/590.40 = 388.92/x
  3. Step 3: Cross multiply
    391.08x = 590.40 × 388.92
  4. Step 4: Simplify right side
    391.08x = 229,618.37
  5. Step 5: Solve for x
    x = 229,618.37/391.08
  6. Step 6: Final answer
    x = 587.14

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.