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Finding the Third Proportional to 511.25 and 780.38

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Solution

The third proportional to 511.25 and 780.38 is: 1,191.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.25 : 780.38 = 780.38 : x
  2. Step 2: Convert to fraction form
    511.25/780.38 = 780.38/x
  3. Step 3: Cross multiply
    511.25x = 780.38 × 780.38
  4. Step 4: Simplify right side
    511.25x = 608,985.14
  5. Step 5: Solve for x
    x = 608,985.14/511.25
  6. Step 6: Final answer
    x = 1,191.17

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Why These Related Problems?

These problems maintain the same ratio (1.53) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.