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Finding the Fourth Proportional to 429.01, 643.78 and 155.16

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Solution

The fourth proportional to 429.01, 643.78 and 155.16 is: 232.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.01 : 643.78 = 155.16 : x
  2. Step 2: Convert to fraction form
    429.01/643.78 = 155.16/x
  3. Step 3: Cross multiply
    429.01x = 643.78 × 155.16
  4. Step 4: Simplify right side
    429.01x = 99,888.90
  5. Step 5: Solve for x
    x = 99,888.90/429.01
  6. Step 6: Final answer
    x = 232.84

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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.