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Finding the Fourth Proportional to 391.79, 540.65 and 298.60

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Solution

The fourth proportional to 391.79, 540.65 and 298.60 is: 412.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.79 : 540.65 = 298.60 : x
  2. Step 2: Convert to fraction form
    391.79/540.65 = 298.60/x
  3. Step 3: Cross multiply
    391.79x = 540.65 × 298.60
  4. Step 4: Simplify right side
    391.79x = 161,437.48
  5. Step 5: Solve for x
    x = 161,437.48/391.79
  6. Step 6: Final answer
    x = 412.05

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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.