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Finding the Fourth Proportional to 428.04, 642.15 and 154.22

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Solution

The fourth proportional to 428.04, 642.15 and 154.22 is: 231.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.04 : 642.15 = 154.22 : x
  2. Step 2: Convert to fraction form
    428.04/642.15 = 154.22/x
  3. Step 3: Cross multiply
    428.04x = 642.15 × 154.22
  4. Step 4: Simplify right side
    428.04x = 99,029.16
  5. Step 5: Solve for x
    x = 99,029.16/428.04
  6. Step 6: Final answer
    x = 231.35

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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.