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Finding the Third Proportional to 780 and 877.50

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Solution

The third proportional to 780 and 877.50 is: 987.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    780 : 877.50 = 877.50 : x
  2. Step 2: Convert to fraction form
    780/877.50 = 877.50/x
  3. Step 3: Cross multiply
    780x = 877.50 × 877.50
  4. Step 4: Simplify right side
    780x = 770,006.25
  5. Step 5: Solve for x
    x = 770,006.25/780
  6. Step 6: Final answer
    x = 987.19

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Why These Related Problems?

These problems maintain the same ratio (1.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.