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Finding the Fourth Proportional to 391.68, 540.80 and 304.32

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Solution

The fourth proportional to 391.68, 540.80 and 304.32 is: 420.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.68 : 540.80 = 304.32 : x
  2. Step 2: Convert to fraction form
    391.68/540.80 = 304.32/x
  3. Step 3: Cross multiply
    391.68x = 540.80 × 304.32
  4. Step 4: Simplify right side
    391.68x = 164,576.26
  5. Step 5: Solve for x
    x = 164,576.26/391.68
  6. Step 6: Final answer
    x = 420.18

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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.