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Finding the Fourth Proportional to 429.58, 643.73 and 256.28

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Solution

The fourth proportional to 429.58, 643.73 and 256.28 is: 384.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.58 : 643.73 = 256.28 : x
  2. Step 2: Convert to fraction form
    429.58/643.73 = 256.28/x
  3. Step 3: Cross multiply
    429.58x = 643.73 × 256.28
  4. Step 4: Simplify right side
    429.58x = 164,975.12
  5. Step 5: Solve for x
    x = 164,975.12/429.58
  6. Step 6: Final answer
    x = 384.04

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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.