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Finding the Fourth Proportional to 640.88, 880.56 and 509.66

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Solution

The fourth proportional to 640.88, 880.56 and 509.66 is: 700.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.88 : 880.56 = 509.66 : x
  2. Step 2: Convert to fraction form
    640.88/880.56 = 509.66/x
  3. Step 3: Cross multiply
    640.88x = 880.56 × 509.66
  4. Step 4: Simplify right side
    640.88x = 448,781.81
  5. Step 5: Solve for x
    x = 448,781.81/640.88
  6. Step 6: Final answer
    x = 700.26

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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.