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Finding the Fourth Proportional to 428.94, 642.18 and 298.64

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Solution

The fourth proportional to 428.94, 642.18 and 298.64 is: 447.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.94 : 642.18 = 298.64 : x
  2. Step 2: Convert to fraction form
    428.94/642.18 = 298.64/x
  3. Step 3: Cross multiply
    428.94x = 642.18 × 298.64
  4. Step 4: Simplify right side
    428.94x = 191,777.42
  5. Step 5: Solve for x
    x = 191,777.42/428.94
  6. Step 6: Final answer
    x = 447.10

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.