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Finding the Fourth Proportional to 780.81, 1,078.04 and 501.17

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Solution

The fourth proportional to 780.81, 1,078.04 and 501.17 is: 691.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.81 : 1,078.04 = 501.17 : x
  2. Step 2: Convert to fraction form
    780.81/1,078.04 = 501.17/x
  3. Step 3: Cross multiply
    780.81x = 1,078.04 × 501.17
  4. Step 4: Simplify right side
    780.81x = 540,273.41
  5. Step 5: Solve for x
    x = 540,273.41/780.81
  6. Step 6: Final answer
    x = 691.94

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.