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Finding the Fourth Proportional to 806.61, 1,210.43 and 319.67

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Solution

The fourth proportional to 806.61, 1,210.43 and 319.67 is: 479.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.61 : 1,210.43 = 319.67 : x
  2. Step 2: Convert to fraction form
    806.61/1,210.43 = 319.67/x
  3. Step 3: Cross multiply
    806.61x = 1,210.43 × 319.67
  4. Step 4: Simplify right side
    806.61x = 386,938.16
  5. Step 5: Solve for x
    x = 386,938.16/806.61
  6. Step 6: Final answer
    x = 479.71

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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.