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Finding the Fourth Proportional to 391.41, 540.77 and 388.67

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Solution

The fourth proportional to 391.41, 540.77 and 388.67 is: 536.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.41 : 540.77 = 388.67 : x
  2. Step 2: Convert to fraction form
    391.41/540.77 = 388.67/x
  3. Step 3: Cross multiply
    391.41x = 540.77 × 388.67
  4. Step 4: Simplify right side
    391.41x = 210,176.43
  5. Step 5: Solve for x
    x = 210,176.43/391.41
  6. Step 6: Final answer
    x = 536.97

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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.