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Finding the Fourth Proportional to 428.88, 591.86 and 318.51

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Solution

The fourth proportional to 428.88, 591.86 and 318.51 is: 439.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.88 : 591.86 = 318.51 : x
  2. Step 2: Convert to fraction form
    428.88/591.86 = 318.51/x
  3. Step 3: Cross multiply
    428.88x = 591.86 × 318.51
  4. Step 4: Simplify right side
    428.88x = 188,511.74
  5. Step 5: Solve for x
    x = 188,511.74/428.88
  6. Step 6: Final answer
    x = 439.54

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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.