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Finding the Fourth Proportional to 640.72, 955.76 and 538.66

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Solution

The fourth proportional to 640.72, 955.76 and 538.66 is: 803.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.72 : 955.76 = 538.66 : x
  2. Step 2: Convert to fraction form
    640.72/955.76 = 538.66/x
  3. Step 3: Cross multiply
    640.72x = 955.76 × 538.66
  4. Step 4: Simplify right side
    640.72x = 514,829.68
  5. Step 5: Solve for x
    x = 514,829.68/640.72
  6. Step 6: Final answer
    x = 803.52

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.