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Finding the Fourth Proportional to 811.07, 1,119.31 and 479.78

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Solution

The fourth proportional to 811.07, 1,119.31 and 479.78 is: 662.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.07 : 1,119.31 = 479.78 : x
  2. Step 2: Convert to fraction form
    811.07/1,119.31 = 479.78/x
  3. Step 3: Cross multiply
    811.07x = 1,119.31 × 479.78
  4. Step 4: Simplify right side
    811.07x = 537,024.15
  5. Step 5: Solve for x
    x = 537,024.15/811.07
  6. Step 6: Final answer
    x = 662.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.