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Finding the Fourth Proportional to 811.15, 1,119.43 and 479.50

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Solution

The fourth proportional to 811.15, 1,119.43 and 479.50 is: 661.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.15 : 1,119.43 = 479.50 : x
  2. Step 2: Convert to fraction form
    811.15/1,119.43 = 479.50/x
  3. Step 3: Cross multiply
    811.15x = 1,119.43 × 479.50
  4. Step 4: Simplify right side
    811.15x = 536,764.49
  5. Step 5: Solve for x
    x = 536,764.49/811.15
  6. Step 6: Final answer
    x = 661.73

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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.