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Finding the Fourth Proportional to 780.47, 1,077.19 and 615.97

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Solution

The fourth proportional to 780.47, 1,077.19 and 615.97 is: 850.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.47 : 1,077.19 = 615.97 : x
  2. Step 2: Convert to fraction form
    780.47/1,077.19 = 615.97/x
  3. Step 3: Cross multiply
    780.47x = 1,077.19 × 615.97
  4. Step 4: Simplify right side
    780.47x = 663,516.72
  5. Step 5: Solve for x
    x = 663,516.72/780.47
  6. Step 6: Final answer
    x = 850.15

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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.