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Finding the Fourth Proportional to 815.07, 1,222.09 and 621.32

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Solution

The fourth proportional to 815.07, 1,222.09 and 621.32 is: 931.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.07 : 1,222.09 = 621.32 : x
  2. Step 2: Convert to fraction form
    815.07/1,222.09 = 621.32/x
  3. Step 3: Cross multiply
    815.07x = 1,222.09 × 621.32
  4. Step 4: Simplify right side
    815.07x = 759,310.46
  5. Step 5: Solve for x
    x = 759,310.46/815.07
  6. Step 6: Final answer
    x = 931.59

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.