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Finding the Fourth Proportional to 807.81, 1,212.79 and 479.36

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Solution

The fourth proportional to 807.81, 1,212.79 and 479.36 is: 719.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.81 : 1,212.79 = 479.36 : x
  2. Step 2: Convert to fraction form
    807.81/1,212.79 = 479.36/x
  3. Step 3: Cross multiply
    807.81x = 1,212.79 × 479.36
  4. Step 4: Simplify right side
    807.81x = 581,356.95
  5. Step 5: Solve for x
    x = 581,356.95/807.81
  6. Step 6: Final answer
    x = 719.67

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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.