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Finding the Fourth Proportional to 678.08, 1,015.29 and 433.86

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Solution

The fourth proportional to 678.08, 1,015.29 and 433.86 is: 649.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.08 : 1,015.29 = 433.86 : x
  2. Step 2: Convert to fraction form
    678.08/1,015.29 = 433.86/x
  3. Step 3: Cross multiply
    678.08x = 1,015.29 × 433.86
  4. Step 4: Simplify right side
    678.08x = 440,493.72
  5. Step 5: Solve for x
    x = 440,493.72/678.08
  6. Step 6: Final answer
    x = 649.62

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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.