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Finding the Fourth Proportional to 811.35, 1,119.69 and 479.79

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Solution

The fourth proportional to 811.35, 1,119.69 and 479.79 is: 662.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.35 : 1,119.69 = 479.79 : x
  2. Step 2: Convert to fraction form
    811.35/1,119.69 = 479.79/x
  3. Step 3: Cross multiply
    811.35x = 1,119.69 × 479.79
  4. Step 4: Simplify right side
    811.35x = 537,216.07
  5. Step 5: Solve for x
    x = 537,216.07/811.35
  6. Step 6: Final answer
    x = 662.13

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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.