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Finding the Fourth Proportional to 431.45, 645.81 and 340.32

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Solution

The fourth proportional to 431.45, 645.81 and 340.32 is: 509.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.45 : 645.81 = 340.32 : x
  2. Step 2: Convert to fraction form
    431.45/645.81 = 340.32/x
  3. Step 3: Cross multiply
    431.45x = 645.81 × 340.32
  4. Step 4: Simplify right side
    431.45x = 219,783.20
  5. Step 5: Solve for x
    x = 219,783.20/431.45
  6. Step 6: Final answer
    x = 509.41

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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.