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Finding the Fourth Proportional to 640.50, 880.06 and 509.28

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Solution

The fourth proportional to 640.50, 880.06 and 509.28 is: 699.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.50 : 880.06 = 509.28 : x
  2. Step 2: Convert to fraction form
    640.50/880.06 = 509.28/x
  3. Step 3: Cross multiply
    640.50x = 880.06 × 509.28
  4. Step 4: Simplify right side
    640.50x = 448,194.41
  5. Step 5: Solve for x
    x = 448,194.41/640.50
  6. Step 6: Final answer
    x = 699.76

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.