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Finding the Fourth Proportional to 779.05, 1,170.20 and 657.55

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Solution

The fourth proportional to 779.05, 1,170.20 and 657.55 is: 987.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.05 : 1,170.20 = 657.55 : x
  2. Step 2: Convert to fraction form
    779.05/1,170.20 = 657.55/x
  3. Step 3: Cross multiply
    779.05x = 1,170.20 × 657.55
  4. Step 4: Simplify right side
    779.05x = 769,465.01
  5. Step 5: Solve for x
    x = 769,465.01/779.05
  6. Step 6: Final answer
    x = 987.70

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.