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Finding the Fourth Proportional to 815.11, 1,123.57 and 618.28

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Solution

The fourth proportional to 815.11, 1,123.57 and 618.28 is: 852.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.11 : 1,123.57 = 618.28 : x
  2. Step 2: Convert to fraction form
    815.11/1,123.57 = 618.28/x
  3. Step 3: Cross multiply
    815.11x = 1,123.57 × 618.28
  4. Step 4: Simplify right side
    815.11x = 694,685.14
  5. Step 5: Solve for x
    x = 694,685.14/815.11
  6. Step 6: Final answer
    x = 852.26

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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.