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Finding the Fourth Proportional to 809.89, 1,214.73 and 419.67

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Solution

The fourth proportional to 809.89, 1,214.73 and 419.67 is: 629.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.89 : 1,214.73 = 419.67 : x
  2. Step 2: Convert to fraction form
    809.89/1,214.73 = 419.67/x
  3. Step 3: Cross multiply
    809.89x = 1,214.73 × 419.67
  4. Step 4: Simplify right side
    809.89x = 509,785.74
  5. Step 5: Solve for x
    x = 509,785.74/809.89
  6. Step 6: Final answer
    x = 629.45

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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.