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Finding the Fourth Proportional to 820.53, 1,131.57 and 621.27

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Solution

The fourth proportional to 820.53, 1,131.57 and 621.27 is: 856.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.53 : 1,131.57 = 621.27 : x
  2. Step 2: Convert to fraction form
    820.53/1,131.57 = 621.27/x
  3. Step 3: Cross multiply
    820.53x = 1,131.57 × 621.27
  4. Step 4: Simplify right side
    820.53x = 703,010.49
  5. Step 5: Solve for x
    x = 703,010.49/820.53
  6. Step 6: Final answer
    x = 856.78

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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.