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Finding the Fourth Proportional to 813.08, 1,119.56 and 636.78

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Solution

The fourth proportional to 813.08, 1,119.56 and 636.78 is: 876.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.08 : 1,119.56 = 636.78 : x
  2. Step 2: Convert to fraction form
    813.08/1,119.56 = 636.78/x
  3. Step 3: Cross multiply
    813.08x = 1,119.56 × 636.78
  4. Step 4: Simplify right side
    813.08x = 712,913.42
  5. Step 5: Solve for x
    x = 712,913.42/813.08
  6. Step 6: Final answer
    x = 876.81

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1.5x scale

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.