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Finding the Fourth Proportional to 428.85, 591.66 and 318.51

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Solution

The fourth proportional to 428.85, 591.66 and 318.51 is: 439.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.85 : 591.66 = 318.51 : x
  2. Step 2: Convert to fraction form
    428.85/591.66 = 318.51/x
  3. Step 3: Cross multiply
    428.85x = 591.66 × 318.51
  4. Step 4: Simplify right side
    428.85x = 188,449.63
  5. Step 5: Solve for x
    x = 188,449.63/428.85
  6. Step 6: Final answer
    x = 439.43

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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.