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Finding the Fourth Proportional to 811.80, 1,119.78 and 637.56

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Solution

The fourth proportional to 811.80, 1,119.78 and 637.56 is: 879.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.80 : 1,119.78 = 637.56 : x
  2. Step 2: Convert to fraction form
    811.80/1,119.78 = 637.56/x
  3. Step 3: Cross multiply
    811.80x = 1,119.78 × 637.56
  4. Step 4: Simplify right side
    811.80x = 713,926.94
  5. Step 5: Solve for x
    x = 713,926.94/811.80
  6. Step 6: Final answer
    x = 879.44

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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.