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Finding the Fourth Proportional to 786.79, 1,180.19 and 209.71

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Solution

The fourth proportional to 786.79, 1,180.19 and 209.71 is: 314.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    786.79 : 1,180.19 = 209.71 : x
  2. Step 2: Convert to fraction form
    786.79/1,180.19 = 209.71/x
  3. Step 3: Cross multiply
    786.79x = 1,180.19 × 209.71
  4. Step 4: Simplify right side
    786.79x = 247,497.64
  5. Step 5: Solve for x
    x = 247,497.64/786.79
  6. Step 6: Final answer
    x = 314.57

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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.