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Finding the Fourth Proportional to 391.84, 540.26 and 317.96

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Solution

The fourth proportional to 391.84, 540.26 and 317.96 is: 438.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.84 : 540.26 = 317.96 : x
  2. Step 2: Convert to fraction form
    391.84/540.26 = 317.96/x
  3. Step 3: Cross multiply
    391.84x = 540.26 × 317.96
  4. Step 4: Simplify right side
    391.84x = 171,781.07
  5. Step 5: Solve for x
    x = 171,781.07/391.84
  6. Step 6: Final answer
    x = 438.40

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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.