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Finding the Fourth Proportional to 779.70, 1,169.12 and 388.91

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Solution

The fourth proportional to 779.70, 1,169.12 and 388.91 is: 583.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    779.70 : 1,169.12 = 388.91 : x
  2. Step 2: Convert to fraction form
    779.70/1,169.12 = 388.91/x
  3. Step 3: Cross multiply
    779.70x = 1,169.12 × 388.91
  4. Step 4: Simplify right side
    779.70x = 454,674.67
  5. Step 5: Solve for x
    x = 454,674.67/779.70
  6. Step 6: Final answer
    x = 583.14

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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.