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Finding the Fourth Proportional to 815.28, 1,125.60 and 628.44

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Solution

The fourth proportional to 815.28, 1,125.60 and 628.44 is: 867.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    815.28 : 1,125.60 = 628.44 : x
  2. Step 2: Convert to fraction form
    815.28/1,125.60 = 628.44/x
  3. Step 3: Cross multiply
    815.28x = 1,125.60 × 628.44
  4. Step 4: Simplify right side
    815.28x = 707,372.06
  5. Step 5: Solve for x
    x = 707,372.06/815.28
  6. Step 6: Final answer
    x = 867.64

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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.