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Finding the Fourth Proportional to 1,138.69, 1,707.49 and 408.30

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Solution

The fourth proportional to 1,138.69, 1,707.49 and 408.30 is: 612.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,138.69 : 1,707.49 = 408.30 : x
  2. Step 2: Convert to fraction form
    1,138.69/1,707.49 = 408.30/x
  3. Step 3: Cross multiply
    1,138.69x = 1,707.49 × 408.30
  4. Step 4: Simplify right side
    1,138.69x = 697,168.17
  5. Step 5: Solve for x
    x = 697,168.17/1,138.69
  6. Step 6: Final answer
    x = 612.25

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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.