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Finding the Fourth Proportional to 428.00, 642.26 and 154.07

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Solution

The fourth proportional to 428.00, 642.26 and 154.07 is: 231.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.00 : 642.26 = 154.07 : x
  2. Step 2: Convert to fraction form
    428.00/642.26 = 154.07/x
  3. Step 3: Cross multiply
    428.00x = 642.26 × 154.07
  4. Step 4: Simplify right side
    428.00x = 98,952.58
  5. Step 5: Solve for x
    x = 98,952.58/428.00
  6. Step 6: Final answer
    x = 231.20

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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.