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Finding the Fourth Proportional to 429.51, 643.40 and 342.99

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Solution

The fourth proportional to 429.51, 643.40 and 342.99 is: 513.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.51 : 643.40 = 342.99 : x
  2. Step 2: Convert to fraction form
    429.51/643.40 = 342.99/x
  3. Step 3: Cross multiply
    429.51x = 643.40 × 342.99
  4. Step 4: Simplify right side
    429.51x = 220,678.05
  5. Step 5: Solve for x
    x = 220,678.05/429.51
  6. Step 6: Final answer
    x = 513.79

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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.