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Finding the Third Proportional to 505.09 and 780.15

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Solution

The third proportional to 505.09 and 780.15 is: 1,205.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.09 : 780.15 = 780.15 : x
  2. Step 2: Convert to fraction form
    505.09/780.15 = 780.15/x
  3. Step 3: Cross multiply
    505.09x = 780.15 × 780.15
  4. Step 4: Simplify right side
    505.09x = 608,637.68
  5. Step 5: Solve for x
    x = 608,637.68/505.09
  6. Step 6: Final answer
    x = 1,205.01

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Why These Related Problems?

These problems maintain the same ratio (1.54) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.