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Finding the Fourth Proportional to 429.23, 643.40 and 326.30

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Solution

The fourth proportional to 429.23, 643.40 and 326.30 is: 489.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.23 : 643.40 = 326.30 : x
  2. Step 2: Convert to fraction form
    429.23/643.40 = 326.30/x
  3. Step 3: Cross multiply
    429.23x = 643.40 × 326.30
  4. Step 4: Simplify right side
    429.23x = 209,941.42
  5. Step 5: Solve for x
    x = 209,941.42/429.23
  6. Step 6: Final answer
    x = 489.11

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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.