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Finding the Fourth Proportional to 657.55, 993.79 and 646.21

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Solution

The fourth proportional to 657.55, 993.79 and 646.21 is: 976.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.55 : 993.79 = 646.21 : x
  2. Step 2: Convert to fraction form
    657.55/993.79 = 646.21/x
  3. Step 3: Cross multiply
    657.55x = 993.79 × 646.21
  4. Step 4: Simplify right side
    657.55x = 642,195.45
  5. Step 5: Solve for x
    x = 642,195.45/657.55
  6. Step 6: Final answer
    x = 976.65

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.