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Finding the Fourth Proportional to 428.55, 642.39 and 185.01

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Solution

The fourth proportional to 428.55, 642.39 and 185.01 is: 277.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.55 : 642.39 = 185.01 : x
  2. Step 2: Convert to fraction form
    428.55/642.39 = 185.01/x
  3. Step 3: Cross multiply
    428.55x = 642.39 × 185.01
  4. Step 4: Simplify right side
    428.55x = 118,848.57
  5. Step 5: Solve for x
    x = 118,848.57/428.55
  6. Step 6: Final answer
    x = 277.33

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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.