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Finding the Fourth Proportional to 428.82, 591.48 and 312.72

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Solution

The fourth proportional to 428.82, 591.48 and 312.72 is: 431.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.82 : 591.48 = 312.72 : x
  2. Step 2: Convert to fraction form
    428.82/591.48 = 312.72/x
  3. Step 3: Cross multiply
    428.82x = 591.48 × 312.72
  4. Step 4: Simplify right side
    428.82x = 184,967.63
  5. Step 5: Solve for x
    x = 184,967.63/428.82
  6. Step 6: Final answer
    x = 431.34

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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.