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Finding the Fourth Proportional to 421.30, 578.96 and 402.28

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Solution

The fourth proportional to 421.30, 578.96 and 402.28 is: 552.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.30 : 578.96 = 402.28 : x
  2. Step 2: Convert to fraction form
    421.30/578.96 = 402.28/x
  3. Step 3: Cross multiply
    421.30x = 578.96 × 402.28
  4. Step 4: Simplify right side
    421.30x = 232,904.03
  5. Step 5: Solve for x
    x = 232,904.03/421.30
  6. Step 6: Final answer
    x = 552.82

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.